Income Taxes Reconciliation of Statutory Federal Income Tax Rate and Effective Tax Rate (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Investments, Owned, Federal Income Tax Note [Line Items]
Federal income tax rate		35.00%
Valuation allowance		$ 36.2
Federal income taxes statutory rate		35.00%	35.00%	35.00%
Increase (decrease) in rate as a result of:
State income taxes, net of federal income tax benefit(1)		(40.10%)	2.40%	4.20%
Federal rate change(2)		741.30%	0.00%	0.00%
State rate change		2.10%	(1.10%)	0.00%
Penalties		(0.40%)	0.00%	(0.30%)
Return to provision adjustment		(0.70%)	0.00%	(0.30%)
Uncertain tax provision (federal rate change)		(7.70%)	0.00%	0.00%
Other		(1.80%)	0.00%	(0.10%)
Effective income tax rate		727.70%	36.30%	38.50%
Subsequent Event [Member]
Investments, Owned, Federal Income Tax Note [Line Items]
Federal income tax rate	21.00%

Effective Income Tax Rate Reconciliation Penalties

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Effective Income Tax Rate Reconciliation Return To Provision Adjustment

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Effective Income Tax Reconciliation State Rate Change

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Federal income tax rate

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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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-Publisher FASB
-Name Accounting Standards Codification
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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 applicable to state and local income tax expense (benefit), net of federal tax expense (benefit).

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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 income tax contingencies. Includes, but not limited to, domestic tax contingency, foreign tax contingency, state and local tax contingency, and other contingencies.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset.

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