Fair Value, Unobservable Input Reconciliation (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2016	Jun. 30, 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 or unrealized) included in income	71	(104)
Purchases	3,339	2,284
Settlements	(3,308)	(8,068)
Transfers into level 3	0	11,586
Transfers out of level 3	0	(1,113)
End of period balance	$ 16,895	$ 16,793