Leases - Schedule of Components of Lease Expense (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2019
Finance lease cost:
Total	$ 4,334	$ 13,148
Occupancy/Equipment Expense [Member]
Lessee Lease Description [Line Items]
Operating lease cost	4,280	12,973
Occupancy Expense [Member]
Finance lease cost:
Amortization of right-of-use assets	166	485
Short-term lease cost	1	2
Sub-lease income	(193)	(553)
Interest Expense [Member]
Finance lease cost:
Interest on lease liabilities	$ 80	$ 241