FDIC Shared-Loss Receivable FDIC Shared-Loss Payable (Changes in Payable to FDIC) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
FDIC Shared-Payable [Abstract]
FDIC shared-loss payable	$ 103,487	$ 99,126	$ 101,342	$ 97,008
Accretion expense	1,009	973	3,002	2,890
Adjustments related to changes in assumptions	80	104	232	305
FDIC shared-loss payable	$ 104,576	$ 100,203	$ 104,576	$ 100,203