| **Income Taxes**                     | 6 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  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| **Income Tax Disclosure [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     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| Income Taxes                         | 10. Income TaxesThe reconciliation of income taxes for the three and six month periods ended June 30, 2016 and 2015, computed at the U.S. federal statutory income tax rate, compared to our effective income tax rate, was as follows: Three Months Ended June 30, Six Months Ended June 30,(in millions of dollars)2016 2015 2016 2015Income tax expense computed at U.S. statutory income tax rate (35%)$25.2 $13.7 $24.3 $11.7Interest on Brazilian Tax Assessment0.7 0.7 1.3 1.4Realized foreign exchange net loss on intercompany loans(3.3) — (10.7) —Revaluation of previously held equity interest(14.2) — (14.2) —Correction of deferred tax — (1.6) — (1.6)Miscellaneous1.6 (1.4) 1.9 —Income tax expense as reported$10.0 $11.4 $2.6 $11.5Effective tax rate13.9% 29.2% 3.8% 34.4%For the six months ended June 30, 2016, we recorded an income tax expense of $2.6 million on income before taxes of $69.3 million. For the six months ended June 30, 2015, we reported an income tax expense of $11.5 million on income before taxes of $33.4 million. The low effective tax rate for the six months ended June 30, 2016 is primarily due to the following: 1) under Australian tax laws, there is no tax expense on the $35.2 million gain arising from the PA Acquisition due to the revaluation of the Company's ownership interest to fair value and 2) tax losses on foreign exchange on the repayment of intercompany loans, for which the pre-tax effect is recorded in equity. The U.S. federal statute of limitations remains open for the year 2012 and forward. Foreign and U.S. state jurisdictions have statutes of limitations generally ranging from 2 to 5 years. Years still open to examination by foreign tax authorities in major jurisdictions include Australia (2011 forward), Brazil (2010 forward), Canada (2007 forward) and the U.K. (2014 forward). We are currently under examination in certain foreign jurisdictions.Income Tax AssessmentIn connection with our May 1, 2012 acquisition of Mead Consumer and Office Products Business ("Mead C&OP") we assumed all of the tax liabilities for the acquired foreign operations including Tilibra Produtos de Papelaria Ltda. ("Tilibra"). In December of 2012, the Federal Revenue Department of the Ministry of Finance of Brazil ("FRD") issued a tax assessment (the "Brazilian Tax Assessment") against Tilibra, which challenged the tax deduction of goodwill from Tilibra's taxable income for the year 2007. A second assessment challenging the deduction of goodwill from Tilibra's taxable income for the years 2008, 2009 and 2010 was issued by FRD in October 2013.Tilibra is disputing both of the tax assessments through established administrative procedures. We believe we have meritorious defenses and intend to vigorously contest these matters; however, there can be no assurances that we will ultimately prevail. We are still in the administrative stages of the process to challenge the FRD's tax assessments, and the ultimate outcome will not be determined until the Brazilian tax appeal process is complete, which is expected to take a number of years. In addition, Tilibra's 2011-2012 tax years remain open and subject to audit, and there can be no assurances that we will not receive additional tax assessments regarding the goodwill for one or both of those years. The time limit for issuing an assessment for 2011 expires in December 2016. If the FRD's initial position is ultimately sustained, the amount assessed would materially and adversely affect our cash flow in the year of settlement.Because there is no settled legal precedent on which to base a definitive opinion as to whether we will ultimately prevail, we consider the outcome of this dispute to be uncertain. Since it is not more likely than not that we will prevail, in 2012, we recorded a reserve in the amount of $44.5 million (at December 31, 2012 exchange rates) in consideration of this contingency, of which $43.3 million was recorded as an adjustment to the purchase price and which included the 2007-2012 tax years plus penalties and interest through December 2012. Included in this reserve is an assumption of penalties at 75%, which is the standard penalty. While there is a possibility that a penalty of 150% could be imposed, based on the facts in our case and existing precedent, we believe the likelihood of a 150% penalty being imposed is not more likely than not. In the meantime, we will continue to actively monitor administrative and judicial court decisions and evaluate their impact, if any, on our legal assessment of the ultimate outcome of our case. In addition, we will continue to accrue interest related to this contingency until such time as the outcome is known or until evidence is presented that we are more likely than not to prevail. During the three months ended June 30, 2016 and 2015 we accrued additional interest as a charge to current income tax expense of $0.7 million and $0.7 million, respectively and for the six months ended June 30, 2016 and 2015, we accrued additional interest of $1.3 million and $1.4 million, respectively. At current exchange rates, our accrual through June 30, 2016, including tax, penalties and interest is $36.0 million. |

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| - Definition
The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.
+ References
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