Income Taxes - Federal Statutory Income Tax Rate Reconciliation (Details)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Federal statutory rate	21.00%	35.00%	35.00%
State income taxes, net of federal benefit	6.00%	5.00%	5.00%
Effective Income Tax Rate Reconciliation, Remeasurement of Deferred Taxes, Percent	(0.00%)	6.00%	(0.00%)
Domestic manufacturing deduction	(0.00%)	(3.00%)	(3.00%)
Excess tax benefits	(2.00%)	(3.00%)	(3.00%)
Other	(1.00%)	(1.00%)	(1.00%)
Total	24.00%	27.00%	33.00%

Effective Income Tax Rate Reconciliation, Remeasurement of Deferred Taxes, Percent

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

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

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to changes in the valuation allowance for deferred tax assets.

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