Supplemental Cash Flow Information - Summary of Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Cash paid during the year for:
Interest	$ 120,823	$ 69,289	$ 55,086
Income taxes, net of refunds	40,754	33,268	23,025
Non-cash investing activities (at fair value):
Acquisition of real estate in settlement of loans	3,207	7,023	13,494
Transfers of loans to loans held for sale	$ 36,627	$ 16,206	318,868
Acquisition of net profits interest in settlement of loans			$ 19,104