Revenue Recognition (Contract with Customer, Asset and Liability) (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Revenue from Contract with Customer [Abstract]
Accounts Receivable, Net	$ 1,019,499	$ 926,089
Contract with Customer, Asset, Net, Current	5,460	0
Contract with Customer, Asset, Net, Noncurrent	6,598	0
Contract with Customer, Liability, Current	$ 62,191	$ 46,433

For an unclassified balance sheet, the amount due from customers or clients for goods or services that have been delivered or sold in the normal course of business, reduced to their estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
-Paragraph 1
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- Definition

+ References

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
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- References

No definition available.

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