Notes Payable - Schedule of Interest Rates and Interest Expense (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Feb. 09, 2016
Long-Term Debt [Line Items]
Line of credit facility, unused capacity, commitment fee percentage	0.50%	0.50%
Interest expense and service fees	$ 29,519	$ 34,224
Amortization of deferred financing fees	1,853	1,733
Amortization of original issue discounts	1,184	1,087
Amortization of net present value of deferred consideration	24	61
Gain on extinguishment of debt	(11)	0
Other interest expense	165	109
Interest expense	$ 32,734	$ 37,214
Notes
Long-Term Debt [Line Items]
Interest rate, stated percentage	10.875%	10.875%	10.875%
Minimum
Long-Term Debt [Line Items]
Debt instrument LIBOR rate	5.36%	6.23%
Maximum
Long-Term Debt [Line Items]
Debt instrument LIBOR rate	5.67%	6.44%