Income Taxes - Reconciliation of Effectoive Income Tax Rate (Details)	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Income Tax Disclosure [Abstract]
Federal statutory rate	21.00%	21.00%	21.00%	21.00%
State income taxes, net of federal benefit	4.20%	3.80%	4.10%	4.60%
Redeemable noncontrolling interests	7.60%	0.00%	1.90%	0.00%
Tax credits	6.90%	3.80%	4.30%	2.40%
Restricted share vesting	(1.00%)	(1.30%)	(3.10%)	(1.80%)
Effect of deferred revaluation related to lower blended state tax rate	0.00%	(3.80%)	0.00%	(1.30%)
Effect of Optimal Blue acquisition and related transactions	9.50%	0.00%	2.30%	0.00%
Non-deductible executive compensation	1.50%	0.00%	1.00%	0.00%
Other	0.30%	0.10%	0.20%	0.40%
Effective tax rate (as a percent)	36.20%	16.00%	23.10%	20.50%

Effective Income Tax Rate Reconciliation, Acquisition, Percent

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Effective Income Tax Rate Reconciliation, Effect of Deferred Revaluation Related to Lower Blended State Tax Rate, Percent

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Effective Income Tax Rate Reconciliation, Nondeductible Expense, Executive Compensation, 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 noncontrolling interest income (loss) exempt from income taxes.

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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 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 expense for award under share-based payment arrangement. Excludes expense determined to be nondeductible upon grant or after for award under share-based payment arrangement.

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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 tax credits. Including, but not limited to, research credit, foreign tax credit, investment tax credit, and other tax credits.

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