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Summary of Significant Accounting Policies - Additional Information (Details) | 3 Months Ended | 12 Months Ended |  |  |
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Dec. 31, 2018 USD ($) | Sep. 30, 2018 | Jun. 30, 2018 | Mar. 31, 2018 | Dec. 31, 2017 USD ($) | Sep. 30, 2017 | Dec. 31, 2018 USD ($) a | Dec. 31, 2017 USD ($) | Dec. 31, 2016 USD ($) | Jan. 01, 2019 USD ($) | Jan. 01, 2018 USD ($) | Dec. 31, 2015 USD ($)
Summary of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Research and development costs |  |  |  |  |  |  | $ 14,400,000 | $ 12,800,000 | $ 13,300,000 |  |  |
Cash and cash equivalents | $ 361,500,000 |  |  |  | $ 216,900,000 |  | 361,500,000 | 216,900,000 | 239,300,000 |  |  | $ 184,200,000
Cash equivalents | 311,100,000 |  |  |  | 160,200,000 |  | 311,100,000 | 160,200,000 |  |  |  |
Allowance for doubtful accounts | 4,600,000 |  |  |  | 4,200,000 |  | $ 4,600,000 | 4,200,000 |  |  |  |
Customer returns, allowances and earned discounts as a percentage of gross selling price |  |  |  |  |  |  | 1.00% |  |  |  |  |
Reserve for customer accounts receivable, percentage |  |  |  |  |  |  | 1.00% |  |  |  |  |
Reserve for customer deductions |  |  |  |  |  |  | $ 9,000,000 | 8,400,000 |  |  |  |
Interest capitalization, construction in progress |  |  |  |  |  |  | 4,500,000 | 2,500,000 | 2,500,000 |  |  |
Depreciation expense |  |  |  |  |  |  | 361,700,000 | 347,800,000 | 324,100,000 |  |  |
Incremental depreciation |  |  |  |  |  |  | $ 14,500,000 | $ 10,500,000 | 2,900,000 |  |  |
Intangible asset, useful life, in years |  |  |  |  |  |  | 10 years 9 months 18 days | 11 years 8 months 12 days |  |  |  |
Goodwill | 917,300,000 |  |  |  | 883,200,000 |  | $ 917,300,000 | $ 883,200,000 | 737,900,000 |  |  |
Goodwill and intangible asset impairment |  |  |  |  |  |  | 0 | 0 | 0 |  |  |
Deferred financing costs | 12,600,000 |  |  |  | 15,300,000 |  | $ 12,600,000 | 15,300,000 |  |  |  |
Area leased under timberland cutting rights (acres) | a |  |  |  |  |  |  | 75,000 |  |  |  |  |
Area leased where fiber farms are operated (acres) | a |  |  |  |  |  |  | 3,000 |  |  |  |  |
Depletion expense |  |  |  |  |  |  | $ 7,600,000 | 5,200,000 | 4,700,000 |  |  |
Net loss on impairment of assets |  |  |  |  |  |  | 3,100,000 | 13,500,000 |  |  |  |
Software amortization expense |  |  |  |  |  |  | 2,100,000 | 2,300,000 | 2,500,000 |  |  |
Retained earnings | 2,315,800,000 |  |  |  | 1,867,400,000 |  | 2,315,800,000 | 1,867,400,000 |  |  |  |
Cost of sales |  |  |  |  |  |  | 5,369,300,000 | 4,974,100,000 | 4,502,900,000 |  |  |
Other long-term assets |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Long-term lease costs capitalization (Cutting rights and Fiber farms) | 22,400,000 |  |  |  | 31,500,000 |  | 22,400,000 | 31,500,000 |  |  |  |
Net capitalized software costs | 1,600,000 |  |  |  | 3,300,000 |  | 1,600,000 | 3,300,000 |  |  |  |
Adjustments for New Accounting Pronouncement | Long-term debt |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Deferred financing costs | $ 12,600,000 |  |  |  | $ 15,300,000 |  | 12,600,000 | 15,300,000 |  |  |  |
ASU 2014-09 | Difference between Revenue Guidance in Effect before and after Topic 606 |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Retained earnings |  |  |  |  |  |  |  |  |  |  | $ 1,600,000 |
Cost of sales |  |  |  |  |  |  | $ 28,200,000 |  |  |  |  |
ASU 2017-07 |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Reclassification of components of income from operation and interest expense, net and other |  |  |  |  |  |  |  | $ 1,300,000 | $ 3,000,000 |  |  |
Customer Relationships |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Intangible asset, useful life, in years |  |  |  |  |  |  | 10 years 10 months 24 days | 11 years 9 months 18 days |  |  |  |
Trademarks and Trade Names |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Intangible asset, useful life, in years |  |  |  |  |  |  | 10 years 1 month 6 days | 9 years 9 months 18 days |  |  |  |
Minimum |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Term of senior credit facilities and notes, in years |  |  |  |  |  |  | 3 years |  |  |  |  |
Minimum | ASU 2016-02 |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Recognition of lease liabilities |  |  |  |  |  |  |  |  |  | $ 220,000,000 |  |
Minimum | Customer Relationships |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Intangible asset, useful life, in years |  |  |  |  |  |  | 10 years |  |  |  |  |
Minimum | Trademarks and Trade Names |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Intangible asset, useful life, in years |  |  |  |  |  |  | 5 years |  |  |  |  |
Maximum |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Term of senior credit facilities and notes, in years |  |  |  |  |  |  | 10 years |  |  |  |  |
Maximum | ASU 2016-02 |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Recognition of lease liabilities |  |  |  |  |  |  |  |  |  | $ 240,000,000 |  |
Maximum | Customer Relationships |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Intangible asset, useful life, in years |  |  |  |  |  |  | 40 years |  |  |  |  |
Maximum | Trademarks and Trade Names |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Intangible asset, useful life, in years |  |  |  |  |  |  | 20 years |  |  |  |  |
Wallula, Washington Mill |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
High-performance of virgin kraft linerboard machine percentage | 100.00% | 100.00% | 100.00% | 100.00% | 100.00% | 100.00% | 100.00% | 100.00% |  |  |  |
Foreign operations |  |  |  |  |  |  |  |  |  |  |  |
Summary of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ 2,300,000 |  |  |  | $ 1,800,000 |  | $ 2,300,000 | $ 1,800,000 |  |  |  |

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