Fair Value Measurements - Liability Measured on Recurring Basis, Unobservable Input Reconciliation (Details) - Contingent Consideration - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 928	$ 1,842	$ 1,024	$ 1,886
Fair value adjustments recorded to income during the period	14	121	57	243
Contingent payments made	(16)	(14)	(183)	(180)
Ending balance	$ 898	$ 1,949	$ 898	$ 1,949