v2.4.0.8

Investment in Joint Ventures (Schedule of Financial Information for Joint Ventures) (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Schedule of Equity Method Investments [Line Items]
Net sale proceeds received from disposition of joint venture			$ 13,410,963	$ 0
Gain on Sale of Interests in Joint Ventures	421,374	0	421,374	0
Condensed Financial Information for the Joint Ventures
Total Revenues	0	0	0	0
Income From Continuing Operations	0	0	0	0
Income (Loss) From Discontinued Operations	289,369	585,125	(1,649,026)	1,826,841
Net Income (Loss)	289,369	585,125	(1,649,026)	1,826,841
Operating Income (Loss)			1,367,131	1,826,841
Impairment Loss			(3,016,157)	0
Fund XI-XII-REIT Associates
Schedule of Equity Method Investments [Line Items]
Net sale proceeds received from disposition of joint venture			599,000
Gain on Sale of Interests in Joint Ventures			13
Condensed Financial Information for the Joint Ventures
Total Revenues	0	0	0	0
Income From Continuing Operations	0	0	0	0
Income (Loss) From Discontinued Operations	13,527	(23,091)	(2,521,656)	(49,210)
Net Income (Loss)	13,527	(23,091)	(2,521,656)	(49,210)
Operating Income (Loss)			(110,605)	(49,210)
Impairment Loss			(2,411,051)	0
Fund XII-REIT Associates
Schedule of Equity Method Investments [Line Items]
Net sale proceeds received from disposition of joint venture			12,812,000
Gain on Sale of Interests in Joint Ventures			421,361
Condensed Financial Information for the Joint Ventures
Total Revenues	0	0	0	0
Income From Continuing Operations	0	0	0	0
Income (Loss) From Discontinued Operations	275,842	608,216	872,630	1,876,051
Net Income (Loss)	275,842	608,216	872,630	1,876,051
Operating Income (Loss)			1,477,736	1,876,051
Impairment Loss			$ (605,106)	$ 0

This item represents the amount of gain (loss) arising from the disposal of an equity method investment.

+ References

No definition available.

+ Details

Name:	us-gaap_EquityMethodInvestmentRealizedGainLossOnDisposal
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

Name:	us-gaap_EquityMethodInvestmentSummarizedFinancialInformationAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount of income (loss) from continuing operations before extraordinary items reported by an equity method investment of the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph g

-Subparagraph 1, 2

-Article 4

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph w

-Article 1

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 18

-Paragraph 20

-Subparagraph d

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 159

-Paragraph 18

-Subparagraph f

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph bb

-Article 1

+ Details

Name:	us-gaap_EquityMethodInvestmentSummarizedFinancialInformationIncomeLossFromContinuingOperationsBeforeExtraordinaryItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The amount of net income (loss) reported by an equity method investment of the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 28

-Subparagraph (f)

-URI http://asc.fasb.org/extlink&oid=6957238&loc=d3e14064-108612

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(g))

-URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e23780-122690

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33912-111571

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph g

-Subparagraph 1, 2

-Article 4

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph w

-Article 1

Reference 7: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 18

-Paragraph 20

-Subparagraph d

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 8: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 159

-Paragraph 18

-Subparagraph f

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 9: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph bb

-Article 1

+ Details

Name:	us-gaap_EquityMethodInvestmentSummarizedFinancialInformationNetIncomeLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The amount of revenue from sale of goods and services reduced by sales returns, allowances, and discounts reported by an equity method investment of the entity.

+ References

No definition available.

+ Details

Name:	us-gaap_EquityMethodInvestmentSummarizedFinancialInformationRevenue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The cash inflow associated with the sale of equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 12

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3179-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 15

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 16

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

Name:	us-gaap_ProceedsFromSaleOfEquityMethodInvestments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	us-gaap_ScheduleOfEquityMethodInvestmentsLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Equity Method Investment, Impairment Loss

+ References

No definition available.

+ Details

Name:	wrefxii_EquityMethodInvestmentImpairmentLoss
Namespace Prefix:	wrefxii_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Equity Method Investment, Income (Loss) from Discontinued Operations

+ References

No definition available.

+ Details

Name:	wrefxii_EquityMethodInvestmentIncomeLossFromDiscontinuedOperations
Namespace Prefix:	wrefxii_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Equity Method Investment, Operating Income (Loss) from Discontinued Operations

+ References

No definition available.

+ Details

Name:	wrefxii_EquityMethodInvestmentOperatingIncomeLossFromDiscontinuedOperations
Namespace Prefix:	wrefxii_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

WELLS REAL ESTATE FUND XII LP 10-Q