Increase (Decrease) Excess Tax Benefit, Share-based-based Compensation And Additional Expenses

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- Definition

Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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

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Amount of reported income tax expense (benefit) in excess of (less than) expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to nondeductible expense for award under share-based payment arrangement. Includes, but is not limited to, expense determined to be nondeductible upon grant or after for award under share-based payment arrangement.

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- Definition

Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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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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No definition available.

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Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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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 - Narrative (Details) - USD ($) shares in Thousands	1 Months Ended		4 Months Ended	9 Months Ended
	Aug. 31, 2019	May 31, 2019	Aug. 31, 2019	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Operating Loss Carryforwards [Line Items]
U.S. federal statutory tax rate (percent)				21.00%	21.00%
Decrease in excess tax benefit, shared-based compensation and additional expenses				$ 13,600,000
Stock Based Compensation, Discrete Tax Benefits				4,400,000	$ 18,000,000.0
Class A common stock repurchased (in shares)	400	1,700	2,072
Deferred Tax Assets, Valuation Allowance				0	0
Unrecognized tax benefits				8,023,000	6,536,000	$ 6,900,000
Unrecognized tax benefits, income tax penalties and interest accrued				400,000	$ 300,000
Federal
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards				34,700,000
State
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards				33,700,000
State \| Latest tax year
Operating Loss Carryforwards [Line Items]
Tax credit carryforwards				14,200,000
State \| Tax year 2023-2027
Operating Loss Carryforwards [Line Items]
Tax credit carryforwards				$ 1,100,000