Revenue - Schedule of Contract Balances (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Revenue from Contract with Customer [Abstract]
Short-term contract assets (included in Prepaid expenses and other current assets)	$ 2,558	$ 2,926
Short-term contract liabilities (included in Other accrued liabilities)	(4,689)	(4,897)
Long-term contract liabilities (included in Noncurrent contract liabilities)	(13,950)	(14,611)
Net contract liabilities	$ (16,081)	$ (16,582)