Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Line Items]
Cash paid for income taxes		$ 515	$ 819	$ 1,062
Deferred tax assets, valuation allowance		$ 2,762	$ 584
Income tax rate at federal statutory rates		35.00%	35.00%	35.00%
Adjustment related to the remeasurement of the deferred tax assets and liability balances		$ 1,808
Tax expense related to nondeductible equity compensation awards		2,901	$ 8,806
Tax expense related to goodwill impairment		17,584
Tax expense (benefit) resulting from adjustment for revaluation of state net operating loss carryforwards			632	$ (1,817)
Scenario Forecast [Member]
Income Tax Disclosure [Line Items]
Income tax rate at federal statutory rates	21.00%
Charitable Contribution Carryforwards [Member]
Income Tax Disclosure [Line Items]
Deferred tax assets, valuation allowance		$ 400
Minimum [Member]
Income Tax Disclosure [Line Items]
Year federal net operating loss carryforwards begin to expire		2029
Ownership shift as defnied by IRC Section 382		50.00%
Federal Tax Credit Carry Forwards [Member]
Income Tax Disclosure [Line Items]
Net operating loss carryforwards		$ 693,000
State Tax Credit Carry Forwards [Member]
Income Tax Disclosure [Line Items]
Net operating loss carryforwards		1,075,000
Deferred tax assets, valuation allowance		$ 2,800	$ 600