Income Taxes - Federal Statutory Income Tax Rate Reconciliation (Details)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Federal statutory rate	21.00%	21.00%	35.00%
State income taxes, net of federal benefit	5.00%	6.00%	5.00%
Remeasurement of deferred taxes	0.00%	0.00%	5.00%
Domestic manufacturing deduction	0.00%	0.00%	(3.00%)
Excess tax benefits	(3.00%)	(2.00%)	(3.00%)
Return to provision	1.00%	0.00%	0.00%
Oklahoma amended tax returns	1.00%	0.00%	0.00%
Other	(1.00%)	(1.00%)	(1.00%)
Total	20.00%	24.00%	28.00%

Effective Income Tax Rate Reconciliation, Amended Tax Return

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

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Effective Income Tax Rate Reconciliation, Return to Provision

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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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