v3.6.0.2

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Statement of Comprehensive Income [Abstract]
Net Income	$ 153,055	$ 139,430	$ 141,148
Defined benefit pension plans (Notes 5 and 10):
Net actuarial gain (loss)	(14,118)	(18,922)	(107,661)
Amortization of prior service cost	828	828	220
Amortization of net actuarial loss	16,781	21,316	14,667
Prior service cost	0	0	(4,130)
Regulatory adjustment	(3,462)	(3,500)	86,991
Net defined benefit pension plans	29	(278)	(9,913)
Forward-starting interest rate swaps:
Amounts reclassified into net income (Notes 5 and 13)	2,075	2,073	2,073
Net forward-starting interest rate swaps	2,075	2,073	2,073
Foreign currency translation adjustments	161	(1,954)	(659)
Total other comprehensive income (loss), net of tax	2,265	(159)	(8,499)
Comprehensive income	155,320	139,271	132,649
Comprehensive income (loss) attributable to noncontrolling interests	1,019	1,047	0
Comprehensive income attributable to Southwest Gas Corporation	$ 154,301	$ 138,224	$ 132,649

The portion of the pension, PBOP, and SERP liability that is recoverable in rates net-of-tax.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income (loss) and other comprehensive income (loss), attributable to noncontrolling interests. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax of cost (credit) of benefit changes attributable to plan participants' prior service resulting from a plan amendment or plan initiation that has not been recognized in net periodic benefit cost (credit).

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Amount after tax of (increase) decrease in the value of the projected benefit obligation related to a change in an actuarial assumption and increase (decrease) in the value of the plan assets resulting from experience different from that assumed, that has not been recognized in net periodic benefit (cost) credit.

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Amount after tax of reclassification adjustment from accumulated other comprehensive (income) loss for prior service cost (credit) related to pension and other postretirement benefit plans.

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Amount after tax and reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount after tax and reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans.

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Amount after tax of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss).

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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SOUTHWEST GAS CORP 10-K