Nature of Operations and Basis of Presentation	3 Months Ended
Mar. 31, 2016
Accounting Policies [Abstract]
Nature of Operations and Basis of Presentation	Nature of Operations and Basis of Presentation GENERAL Clearwater Paper manufactures quality consumer tissue, away-from-home tissue, parent roll tissue, bleached paperboard and pulp at manufacturing facilities across the nation. The company is a premier supplier of private label tissue to major retailers and wholesale distributors, including grocery, drug, mass merchants and discount stores. In addition, the company produces bleached paperboard used by quality-conscious printers and packaging converters. FINANCIAL STATEMENT PREPARATION AND PRESENTATION The accompanying Consolidated Balance Sheets at March 31, 2016 and December 31, 2015, the related Consolidated Statements of Operations and Comprehensive Income for the three months ended March 31, 2016 and 2015, and the Consolidated Statements of Cash Flows for the three months ended March 31, 2016 and 2015, have been prepared in conformity with accounting principles generally accepted in the United States of America, or GAAP. We believe that all adjustments necessary for a fair statement of the results of the interim periods presented have been included. The results of operations for any interim period are not necessarily indicative of the results of operations to be expected for the full year. This Quarterly Report on Form 10-Q should be read in conjunction with our Annual Report on Form 10-K for the year ended December 31, 2015, as filed with the Securities and Exchange Commission, or SEC, on February 22, 2016. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES SIGNIFICANT ESTIMATES The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of net sales and expenses during the reporting periods. Significant areas requiring the use of estimates and measurement of uncertainty include determination of net realizable value for deferred tax assets, uncertain tax positions, assessment of impairment of long-lived assets, goodwill and intangibles, assessment of environmental matters, equity-based compensation and pension and postretirement obligation assumptions. Actual results could differ from those estimates and assumptions. CASH AND CASH EQUIVALENTS We consider all highly liquid instruments with maturities of three months or less to be cash equivalents. SHORT-TERM INVESTMENTS AND RESTRICTED CASH Our short-term investments are invested primarily in demand deposits, which have very short maturity periods, and therefore earn an interest rate commensurate with low-risk instruments. We do not attempt to hedge our exposure to interest rate risk for our short-term investments. Our restricted cash in which the underlying instrument has a term of greater than twelve months from the balance sheet date is classified as non-current and is included in “Other assets, net” on our Consolidated Balance Sheet. As of both March 31, 2016 and December 31, 2015, we had $2.3 million classified as current on our Consolidated Balance Sheet. TRADE ACCOUNTS RECEIVABLE Trade accounts receivable are stated at the amount we expect to collect. Trade accounts receivable do not bear interest. The allowance for doubtful accounts is our best estimate of the losses we expect will result from the inability of our customers to make required payments. We generally determine the allowance based on a combination of actual historical write-off experience and an analysis of specific customer accounts. As of March 31, 2016 and December 31, 2015, we had allowances for doubtful accounts of $1.7 million and $1.4 million, respectively. PROPERTY, PLANT AND EQUIPMENT Property, plant and equipment are stated at cost, including any interest costs capitalized, less accumulated depreciation. Depreciation of buildings, equipment and other depreciable assets is determined using the straight-line method. Assets we acquire through business combinations have estimated lives that are typically shorter than the assets we construct or buy new. Accumulated depreciation totaled $1,532.2 million and $1,512.1 million at March 31, 2016 and December 31, 2015, respectively. Consistent with authoritative guidance, we assess the carrying amount of long-lived assets with definite lives that are held-for-use and evaluate them for recoverability whenever events or changes in circumstances indicate that we may be unable to recover the carrying amount of the assets. STOCKHOLDERS’ EQUITY On December 15, 2015, we announced that our Board of Directors had approved a new stock repurchase program authorizing the repurchase of up to $100 million of our common stock. The repurchase program authorizes purchases of our common stock from time to time through open market purchases, negotiated transactions or other means, including accelerated stock repurchases and 10b5-1 trading plans in accordance with applicable securities laws and other restrictions. We have no obligation to repurchase stock under this program and may suspend or terminate the program at any time. During the first quarter of 2016, we repurchased 709,366 shares of our outstanding common stock at an average price of $38.99 per share. As of March 31, 2016, we had up to $72.3 million of authorization remaining pursuant to this stock repurchase program. On December 15, 2014, we announced that our Board of Directors had approved a stock repurchase program authorizing the repurchase of up to $100 million of our common stock. We completed that program during the fourth quarter of 2015. In total, we repurchased 1,881,921 shares of our outstanding common stock under that program at an average price of $53.13 per share. DERIVATIVES We had no activity during the three months ended March 31, 2016 and 2015 that required hedge or derivative accounting treatment. However, to help mitigate our exposure to market risk for changes in utility commodity pricing, we use firm price contracts to supply a portion of the natural gas requirements for our manufacturing facilities. As of March 31, 2016, these contracts covered approximately 43% of our expected average monthly natural gas requirements for the remainder of 2016. Historically, these contracts have qualified for treatment as “normal purchases or normal sales” under authoritative guidance and thus required no mark-to-market adjustment.

Nature of Operations and Basis of Presentation

GENERAL

Clearwater Paper manufactures quality consumer tissue, away-from-home tissue, parent roll tissue, bleached paperboard and pulp at manufacturing facilities across the nation. The company is a premier supplier of private label tissue to major retailers and wholesale distributors, including grocery, drug, mass merchants and discount stores. In addition, the company produces bleached paperboard used by quality-conscious printers and packaging converters.

FINANCIAL STATEMENT PREPARATION AND PRESENTATION

The accompanying Consolidated Balance Sheets at March 31, 2016 and December 31, 2015, the related Consolidated Statements of Operations and Comprehensive Income for the three months ended March 31, 2016 and 2015, and the Consolidated Statements of Cash Flows for the three months ended March 31, 2016 and 2015, have been prepared in conformity with accounting principles generally accepted in the United States of America, or GAAP. We believe that all adjustments necessary for a fair statement of the results of the interim periods presented have been included. The results of operations for any interim period are not necessarily indicative of the results of operations to be expected for the full year.

This Quarterly Report on Form 10-Q should be read in conjunction with our Annual Report on Form 10-K for the year ended December 31, 2015, as filed with the Securities and Exchange Commission, or SEC, on February 22, 2016.

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

SIGNIFICANT ESTIMATES

The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of net sales and expenses during the reporting periods. Significant areas requiring the use of estimates and measurement of uncertainty include determination of net realizable value for deferred tax assets, uncertain tax positions, assessment of impairment of long-lived assets, goodwill and intangibles, assessment of environmental matters, equity-based compensation and pension and postretirement obligation assumptions. Actual results could differ from those estimates and assumptions.

CASH AND CASH EQUIVALENTS

We consider all highly liquid instruments with maturities of three months or less to be cash equivalents.

SHORT-TERM INVESTMENTS AND RESTRICTED CASH

Our short-term investments are invested primarily in demand deposits, which have very short maturity periods, and therefore earn an interest rate commensurate with low-risk instruments. We do not attempt to hedge our exposure to interest rate risk for our short-term investments. Our restricted cash in which the underlying instrument has a term of greater than twelve months from the balance sheet date is classified as non-current and is included in “Other assets, net” on our Consolidated Balance Sheet. As of both March 31, 2016 and December 31, 2015, we had $2.3 million classified as current on our Consolidated Balance Sheet.

TRADE ACCOUNTS RECEIVABLE

Trade accounts receivable are stated at the amount we expect to collect. Trade accounts receivable do not bear interest. The allowance for doubtful accounts is our best estimate of the losses we expect will result from the inability of our customers to make required payments. We generally determine the allowance based on a combination of actual historical write-off experience and an analysis of specific customer accounts. As of March 31, 2016 and December 31, 2015, we had allowances for doubtful accounts of $1.7 million and $1.4 million, respectively.

PROPERTY, PLANT AND EQUIPMENT

Property, plant and equipment are stated at cost, including any interest costs capitalized, less accumulated depreciation. Depreciation of buildings, equipment and other depreciable assets is determined using the straight-line method. Assets we acquire through business combinations have estimated lives that are typically shorter than the assets we construct or buy new. Accumulated depreciation totaled $1,532.2 million and $1,512.1 million at March 31, 2016 and December 31, 2015, respectively.

Consistent with authoritative guidance, we assess the carrying amount of long-lived assets with definite lives that are held-for-use and evaluate them for recoverability whenever events or changes in circumstances indicate that we may be unable to recover the carrying amount of the assets.

STOCKHOLDERS’ EQUITY

On December 15, 2015, we announced that our Board of Directors had approved a new stock repurchase program authorizing the repurchase of up to $100 million of our common stock. The repurchase program authorizes purchases of our common stock from time to time through open market purchases, negotiated transactions or other means, including accelerated stock repurchases and 10b5-1 trading plans in accordance with applicable securities laws and other restrictions. We have no obligation to repurchase stock under this program and may suspend or terminate the program at any time. During the first quarter of 2016, we repurchased 709,366 shares of our outstanding common stock at an average price of $38.99 per share. As of March 31, 2016, we had up to $72.3 million of authorization remaining pursuant to this stock repurchase program.

On December 15, 2014, we announced that our Board of Directors had approved a stock repurchase program authorizing the repurchase of up to $100 million of our common stock. We completed that program during the fourth quarter of 2015. In total, we repurchased 1,881,921 shares of our outstanding common stock under that program at an average price of $53.13 per share.

DERIVATIVES

We had no activity during the three months ended March 31, 2016 and 2015 that required hedge or derivative accounting treatment. However, to help mitigate our exposure to market risk for changes in utility commodity pricing, we use firm price contracts to supply a portion of the natural gas requirements for our manufacturing facilities. As of March 31, 2016, these contracts covered approximately 43% of our expected average monthly natural gas requirements for the remainder of 2016. Historically, these contracts have qualified for treatment as “normal purchases or normal sales” under authoritative guidance and thus required no mark-to-market adjustment.