Income Taxes - Carryforwards Available to Reduce Future Income Taxes (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($)
U.S. Federal [Member]
Carryforward Available To Reduce Future Income Taxes [Line Items]
Net operating loss, Years of Expiration Carryforward	2019-2037
Net operating loss, Tax Credit Carryforward, Amount	$ 906,317
State Taxes [Member]
Carryforward Available To Reduce Future Income Taxes [Line Items]
Net operating loss, Years of Expiration Carryforward	2020-2037
Net operating loss, Tax Credit Carryforward, Amount	$ 1,538,152
Years of Expiration Carryforward Unlimited
Carryforward Available To Reduce Future Income Taxes [Line Items]
Net operating loss, Tax Credit Carryforward, Amount	3,813
Interest expense, Tax Credit Carryforward, Amount	$ 297,875