SUPPLEMENTAL CASH FLOW INFORMATION - Supplemental Cash Flow Information (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Cash paid for:
Interest on borrowings	$ 25,368	$ 24,353
Income tax	3,412	0
Operating cash flow from operating leases	2,742	0
Non-cash investing and financing activities:
Additions to OREO	12,264	15,867
Additions to auto and other repossessed assets	11,587	17,508
Capitalization of servicing assets	868	887
Loan securitizations	51,034	54,382
Loans held for investment transferred to held for sale	1,775	67,937
Adoption of lease accounting standard:
Right-of-use assets operating leases	57,178	0
Righ-of-use liabilities operating leases	$ 59,818	$ 0