Business Acquisitions - Schedule of Assets Acquired and Liabilities Assumed (Details) - USD ($) $ in Thousands	Oct. 01, 2017	Dec. 31, 2016	Oct. 12, 2016
Business Acquisition [Line Items]
Goodwill	$ 210,685	$ 206,659
Downstream [Member]
Business Acquisition [Line Items]
Cash and cash equivalents			$ 6,603
Accounts receivable			28,128
Unbilled receivable			10,786
Inventory			18,701
Prepaid and other current assets			5,671
Property, plant and equipment			21,214
Intangible assets			101,600
Accounts payable			(11,655)
Accrued and other expenses			(8,866)
Deferred revenue			(3,997)
Deferred income taxes			(40,645)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities Noncurrent			556
Total identifiable net assets			126,984
Goodwill			89,473
Total purchase price			$ 216,457