Cover - USD ($) $ in Millions	12 Months Ended
Cover - USD ($) $ in Millions	Dec. 31, 2024	Feb. 21, 2025	Jun. 30, 2024
Cover [Abstract]
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Document Type	10-K/A
Document Annual Report	true
Document Transition Report	false
Entity File Number	001-34146
Registrant Name	CLEARWATER PAPER CORPORATION
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	20-3594554
Entity Address, Postal Zip Code	99201
Entity Address, Address Line Two	Suite 1100
Entity Address, Address Line One	601 West Riverside,
Entity Address, State or Province	WA
Entity Address, City or Town	Spokane,
City Area Code	509
Local Phone Number	344-5900
Title of 12(b) Security	Common Stock ($0.0001 par value per share)
Trading Symbol	CLW
Security Exchange Name	NYSE
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Document Financial Statement Error Correction [Flag]	false
Entity Shell Company	false
Entity Public Float			$ 788.5
Entity Common Stock, Shares Outstanding		16,175,161
Amendment Description	Clearwater Paper Corporation (the “Company”) is filing this Amendment No. 1 on Form 10-K/A (this “Amendment”) to amend the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2024 (the “Original Filing”), which was originally filed with the U.S. Securities and Exchange Commission (the “SEC”) on February 24, 2025 (the “Original Filing Date”). The sole purpose of this Amendment is to amend the Exhibits contained in Item 15 of Part IV of the Original Filing to include Exhibit 19.1, Clearwater Paper Corporation Insider Trading Policy, which was inadvertently omitted in the Original Filing.This Amendment is an exhibit-only filing. Except as described above, no changes have been made to the Original Filing and this Amendment does not modify, amend, or update in any way any of the financial or other information contained in the Original Filing. This Amendment does not reflect events that may have occurred subsequent to the Original Filing Date. Accordingly, this Amendment should be read in conjunction with the Original Filing and the Company’s other filings with the SEC.Pursuant to Rule 12b-15 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), currently dated certifications are filed herewith as exhibits to this Amendment pursuant to Rule 13a-14(a) or 15d-14(a) of the Exchange Act. These certifications are attached to this Amendment as Exhibit 31.1 under Item 15 of Part IV hereof. Because no financial statements are being filed with this Amendment and this Amendment does not contain any disclosure with respect to Items 307 and 308 of Regulation S-K, paragraphs 3, 4, and 5 of the certifications have been omitted. Similarly, because no financial statements are being filed with this Amendment, certifications pursuant to Section 906 of the Sarbanes-Oxley Act of 2002 have been omitted.
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Document Fiscal Year Focus	2024
Central Index Key	0001441236
Amendment Flag	true
Document Period End Date	Dec. 31, 2024
Document Information [Line Items]
Document Fiscal Period Focus	FY
Document Fiscal Year Focus	2024
Document Period End Date	Dec. 31, 2024
Current Fiscal Year End Date	--12-31

Clearwater Paper Corp 10-K/A