Income Taxes - Reconciliation of the U.S. Federal Statutory Income Tax Rate (Details)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Statutory federal tax (benefit) rate	21.00%	21.00%	35.00%
State income provision (benefit), net of federal	1.40%	1.20%	0.70%
Nondeductible health insurer fee (“HIF”)	0.00%	7.30%	0.00%
Nondeductible compensation	1.20%	0.70%	(2.80%)
Nondeductible goodwill impairment	0.00%	0.00%	(6.60%)
Worthless stock deduction	0.00%	(1.00%)	0.00%
Revaluation of net deferred tax assets	0.00%	(0.40%)	(8.80%)
Other	0.60%	0.40%	(1.10%)
Effective tax expense (benefit) rate	24.20%	29.20%	16.40%

Effective Income Tax Rate Reconciliation, Nondeductible Expense, Health Insurance, Percent

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Effective Income Tax Rate Reconciliation, Worthless Stock Deduction

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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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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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