Fair Value Measurements, Level 3 Unobservable Inputs (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Reconciliation of assets and liabilities measured at fair value using significant unobservable inputs (Level 3) [Roll Forward]
Beginning balance, at fair value	$ 379	$ 483	$ 428	$ 2,345
OTTI impairment losses	0	0	0	0
Principal payments	(29)	(14)	(90)	(149)
Sales	0	0	0	(1,702)
Change in unrealized loss	5	(1)	17	(26)
Ending balance, at fair value	$ 355	$ 468	$ 355	$ 468