Revenue Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Jan. 01, 2018	Dec. 31, 2017
Revenue from Contract with Customer [Abstract]
Average transit time	3 days
Accounts receivable, net	$ 337,927		$ 304,174
Contract assets	7,400	$ 7,800
Contract liabilities	1,700		$ 2,100
Revenue recognized from contract liability during the period	$ 2,100

Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
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-Section 50
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-Publisher FASB
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- 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.

+ References

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

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

+ References

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- References

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- Definition

Average transit time

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No definition available.

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