Estimated effective income tax rate reconciliation federal and state income taxes.

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Income taxes line items.

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Tax Cuts and Jobs Act of 2017, incomplete accounting, change in tax rate, deferred tax liability, provisional income tax benefit .

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Tax Cuts and Jobs Act of 2017, incomplete accounting, change in tax rate, provisional income tax expense (benefit).

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Tax Cuts and Jobs Act of 2017, incomplete accounting, provisional income tax expense (benefit).

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Tax Cuts and Jobs Act of 2017, incomplete accounting, reduction of deductions qualified production activities.

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Tax Cuts and Jobs Act of 2017, incomplete accounting, transition tax for accumulated foreign earnings, provisional income tax expense.

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Tax Cuts And Jobs Act Of 2017, incomplete accounting, transition tax, provisional income tax expense.

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Tax Cuts and Jobs Act of 2017 maximum measurement period to finalize accounting of tax.

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Amount of decrease reasonably possible in the next twelve months for the unrecognized tax benefit.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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A brief description of status of the tax examination, significant findings to date, and the entity's position with respect to the findings.

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The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income.

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Tax year that remains open to examination under enacted tax laws, in CCYY format.

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Amount of unrecognized tax benefits.

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Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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Income Taxes - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Taxes [Line Items]
Federal corporate tax rate		35.00%	35.00%	35.00%
Maximum measurement period to finalize accounting of tax		1 year
Income tax benefit as result of Tax Act		$ 122.1
Re-measurement of deferred tax assets and liabilities due to enacted corporate tax rate		128.0
Reduction in domestic manufacturers deductions		5.1
Transition tax due to tax reform		0.8
Increase in deferred tax liabilities		24.6
Provisional transition tax obligation		0.1
Cash payments for income taxes		298.7	$ 222.1	$ 238.3
Gross reserve for unrecognized tax benefits, excluding interest and penalties		4.8	5.2	$ 5.8	$ 4.4
Unrecognized tax benefits that would impact of effective tax rate		4.2
Interest accrued related to unrecognized tax benefits and penalties		1.1	$ 1.1
Reasonably possible decrease in unrecognized tax benefits related to state apportionment issues in next 12 months		$ 3.1
Internal Revenue Service (IRS)
Income Taxes [Line Items]
Income tax examination (description)		A federal examination of the tax years 2010 - 2012 was concluded in February 2015
Foreign
Income Taxes [Line Items]
Open tax year		2009
Boise Inc.
Income Taxes [Line Items]
Open tax year		2013
Earliest Tax Year \| Internal Revenue Service (IRS)
Income Taxes [Line Items]
Open tax year		2014
Earliest Tax Year \| State taxing jurisdiction
Income Taxes [Line Items]
Open tax year		2013
Earliest Tax Year \| Boise Inc.
Income Taxes [Line Items]
Open tax year		2008
Latest Tax Year \| Internal Revenue Service (IRS)
Income Taxes [Line Items]
Open tax year		2017
Latest Tax Year \| State taxing jurisdiction
Income Taxes [Line Items]
Open tax year		2017
Latest Tax Year \| Boise Inc.
Income Taxes [Line Items]
Open tax year		2011
Minimum
Income Taxes [Line Items]
Estimated federal and state effective tax rate		0.24
Maximum
Income Taxes [Line Items]
Estimated federal and state effective tax rate		0.26
Scenario, Forecast
Income Taxes [Line Items]
Federal corporate tax rate	21.00%