Fair Value Measurements - Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation (Details) - Unobservable Inputs (Level 3) - Fair Value, Measurements, Recurring $ in Thousands	3 Months Ended
	Mar. 31, 2019 USD ($)
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning balance	$ 2,554
Ending balance	1,569
Fair value adjustment to Chiaro contingent consideration
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value adjustment to contingent consideration	75
Fair value adjustment to GVi contingent consideration
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value adjustment to contingent consideration	$ (1,060)