Contract Balances (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Jan. 01, 2018
Revenue from Contract with Customer [Abstract]
Contract assets, net	$ 9,330		$ 11,932
Contract with Customer, Liability, Current	36,461	$ 48,268	48,268
Contract with Customer, Liability, Noncurrent	9,382	9,916	9,916
Change in Contract with Customer, Asset and Liability [Abstract]
Contract assets, net	9,330		11,932
Cumulative catch-up adjustment upon transition	701
Changes in estimate at the stage of completion	11,884
Transferred to receivables from contract assets recognized during the period	(14,947)
Other	(240)
Contract liability, net	45,843		$ 58,184
Revenue recognized during the period	(68,211)	$ 38,410
Increases due to cash received	64,603
Other	$ (8,733)

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Amount of increase (decrease) in revenue recognized for cumulative catch-up adjustment from change in measure of progress which increases (decreases) right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

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Amount of increase (decrease) in right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time, from business combination.

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Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

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Amount of decrease in right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time from transfer to receivable due to right to consideration becoming unconditional.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

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