Disclosures about Fair Value of Assets and Liabilities - Reconcilation of Unobservable Inputs (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Reconciliation of significant unobservable inputs:
Balance, beginning of period	$ 57,557	$ 55,422	$ 53,670	$ 55,553
Additions
Purchased servicing	76	933	1,209	1,252
Originated servicing	2,939	2,379	7,775	3,349
Acquisition of Richmac	3,970		3,970
Subtractions
Paydowns	(1,083)	(1,798)	(3,813)	(3,218)
Changes in fair value due to changes in valuation inputs or assumptions used in the valuation model	(1,437)		(789)
Balance, end of period	$ 62,022	$ 56,936	$ 62,022	$ 56,936