Income Taxes - Income Tax Rate Reconciliation (Details)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Statutory federal tax rate	21.00%	21.00%	21.00%
State and local taxes, net of federal tax benefit	7.40%	2.70%	(6.70%)
Change in value of indemnification asset	2.80%	1.60%	(3.30%)
Non-deductible executive compensation	3.50%	0.00%	0.00%
Stock compensation	4.40%	0.00%	0.00%
Non-deductible transaction costs	4.90%	0.80%	0.00%
Change in valuation allowance	(256.00%)	1.90%	(2.10%)
Change in unrecognized tax benefits (including FBOS)	(48.70%)	5.30%	2.70%
Other, net	(0.30%)	0.40%	2.40%
Effective tax rate	(261.00%)	33.70%	14.00%

Effective Income Tax Rate Reconciliation, Change in Fair Value of Indemnification Asset

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Effective Income Tax Rate Reconciliation, Change In Unrecognized Tax Benefits, Percent

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Effective Income Tax Rate Reconciliation, Nondeductible Expense, Transaction Costs, 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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
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-Paragraph 12
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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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Percentage of difference between reported income tax expense (benefit) and 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 share-based payment arrangement.

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Percentage of the difference, between reported income tax expense (benefit) and the expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations, that is attributable to tax exempt income, equity in earnings (loss) of an unconsolidated subsidiary, minority interest income (expense), tax holiday, disposition of a business, disposition of an asset, repatriation of foreign earnings, repatriation of foreign earnings jobs creation act of 2004, change in enacted tax rate, prior year income taxes, change in deferred tax asset valuation allowance, and other adjustments.

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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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