Fair Value, Unobservable Input Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Fair value assets measured on recurring basis unobservable input reconciliation calculation [Roll Forward]
Beginning of period balance	$ 16,793	$ 12,208
Total gains or losses (realized) included in income	1,846	(104)
Purchases	5,540	2,284
Settlements	(8,791)	(8,068)
Transfers into Level 3	10,202	11,586
Transfers out of Level 3	(372)	(1,113)
End of period balance	$ 25,218	$ 16,793