Revenue from Contracts with Customers - Contract Assets Table (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2019	Dec. 31, 2018
Change in Contracts with Customer, Asset [Roll Forward]
Balance at December 31, 2018	$ 47,621
Amounts transferred to Accounts receivable, net that were included in the contract assets balance at the beginning of the period	(1,574)
Additional estimated revenues recognized	9,951
Balance at June 30, 2019	55,998
Contract assets at June 30, 2019
Other current assets		$ 12,501	$ 5,399
Other assets		43,497
Total contract assets from contracts with customers	$ 47,621	$ 55,998	$ 47,621