Financial Statement Information Schedule of New Accounting Pronouncements (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Jan. 01, 2018	Dec. 31, 2017
New Accounting Pronouncement, Early Adoption [Line Items]
Receivables, Net, Current	$ 1,211,788	$ 1,065,617	$ 1,027,106
Prepaid Expense and Other Assets, Current	180,367	$ 178,987	134,479
Other assets	146,067		142,965
Other current liabilities	41,167		45,727
Deferred Income Taxes	$ (242,226)		$ (252,359)

Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences, with jurisdictional netting and classified as noncurrent.

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