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Revenue from Contracts with Customers Revenue from Contracts with Customers (Details) - USD ($) | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2018 | Jun. 30, 2017 | Jun. 30, 2018 | Jun. 30, 2017
Business Acquisition [Line Items] |  |  |  |  |
Performance obligation satisfied in previous period |  | $ 0 | $ 11,600,000 | $ 0 | $ 18,100,000
Change in estimate of transaction price |  | 0 | 0 | 0 | 0
Change in total estimated costs, measure of progress |  | 0 | 0 | 0 | 0
Loss on contracts |  | 0 | $ 0 | 0 | $ 0
Change in net contract liabilities |  |  |  | 50,100,000 |
Contract asset impairment |  |  |  | 0 |
Remaining performance obligations |  | $ 3,673,131,000 |  | 3,673,131,000 |
Cumulative effect on retained earnings, net of tax | [1] |  |  | 854,000 |
2018 Acquisitions |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Increase (decrease) in contract assets from acquisitions |  |  |  | 300,000 |
Increase (decrease) in contract liabilities from acquisitions |  |  |  | $ 2,100,000 |
[1] | Represents adjustment to retained earnings upon the adoption of Accounting Standards Codification Topic 606.

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- Definition Amount of increase (decrease) in revenue recognized for cumulative catch-up adjustment from change in measure of progress which increases (decreases) right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time. + References No definition available. + Details
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- Definition Amount of increase (decrease) in net contract assets and liabilities. + References No definition available. + Details
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- Definition Amount of revenue recognized from performance obligation satisfied or partially satisfied in previous reporting periods. Includes, but is not limited to, change in transaction price. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 12A -URI http://asc.fasb.org/extlink&oid=109196051&loc=SL108322424-203045 + Details
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