Covered Assets and Indemnification Asset - Covered OREO (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Activity in covered OREO
Balance, beginning of period	$ 36,744	$ 51,642
Additions to covered OREO	2,495	1,723
Dispositions of covered OREO	(2,407)	(6,799)
Valuation adjustments in the period	(1,055)	(1,192)
Balance, end of period	$ 35,777	$ 45,374