Basis of Presentation and Nature of Operations - Schedule of Revenue Calculated under Old and New Accounting Methods (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2018	Dec. 31, 2017
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Revenue	$ 332,968	$ 960,063
Contract assets	143,161	143,161	$ 123,197
Contract liabilities	26,489	26,489	38,571
ASU 2014-09 \| As Reported
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Revenue	331,978	957,773
Contract assets	141,391	141,391	123,197
Contract liabilities	$ 27,009	$ 27,009	$ 38,571

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, classified as current.

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