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Revenue from Contracts with Customers (Details) - USD ($) | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | Dec. 31, 2018
Business Acquisition [Line Items] |  |  |  |  |
Performance obligation satisfied in previous period | $ 0 | $ 0 | $ 0 | $ 0 |
Change in estimate of transaction price | 0 | 0 | 0 | 0 |
Change in total estimated cost | 0 | 0 | 0 | 0 |
Loss on contracts | 0 | $ 0 | 0 | $ 0 |
Change in net contract liabilities |  |  | 29,100,000 |  |
Contract asset impairment |  |  | 0 |  | $ 0
Remaining performance obligations | $ 4,225,995,000 |  | 4,225,995,000 |  |
2019 Acquisitions |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Increase in contract assets from acquisitions |  |  | 5,800,000 |  |
Increase in contract liabilities from acquisitions |  |  | $ 10,500,000 |  |

X
- 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 expense (reversal of expense) for expected credit loss on 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://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919249-210447 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130551-203045 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130543-203045 + Details
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