Income taxes.

No definition available.

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- Definition

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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- Definition

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

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- Definition

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

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- Definition

Amount of unrecognized tax benefits.

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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 ($)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2017
Income Taxes [Line Items]
Effective income tax rate reconciliation, percent	23.60%	22.90%	23.20%	24.00%
Unrecognized tax benefits	$ 0		$ 0
Unrecognized tax benefits that would impact effective tax rate	$ 0		$ 0
Federal corporate income tax rate			21.00%		35.00%
Internal Revenue Service (IRS) \| Earliest Tax Year
Income Taxes [Line Items]
Open tax year			2016
Internal Revenue Service (IRS) \| Latest Tax Year
Income Taxes [Line Items]
Open tax year			2018
State Local and Foreign Jurisdictions \| Earliest Tax Year
Income Taxes [Line Items]
Open tax year			2015
State Local and Foreign Jurisdictions \| Latest Tax Year
Income Taxes [Line Items]
Open tax year			2018