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Revenue from Contracts with Customers Revenue from Contracts with Customers (Details) - USD ($) | 3 Months Ended
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Mar. 31, 2018 | Mar. 31, 2017
Revenue from Contract with Customer [Abstract] |  |  |
Performance obligation satisfied in previous period |  | $ 0 | $ 0
Change in estimate of transaction price |  | 0 | 0
Change in total estimated costs, measure of progress |  | 0 | 0
Loss on contracts |  | 0 | $ 0
Change in net contract liabilities |  | 46,700,000 |
Contract asset impairment |  | 0 |
Remaining performance obligations |  | 3,603,743,000 |
Cumulative effect on retained earnings, net of tax | [1] | $ 854,000 |
[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 credit loss recognized for write-down 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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=82913847&loc=SL49130551-203045 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=82913815&loc=SL49130533-203044 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=82913847&loc=SL49130543-203045 + Details
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- Definition Amount of increase (decrease) in revenue recognized for cumulative catch-up adjustment from change in estimate of transaction price 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. Includes, but is not limited to, change in assessment of whether estimate of variable consideration is constrained. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=82913847&loc=SL49130551-203045 + 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/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 270 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=84173487&loc=SL51747714-108306 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=82913847&loc=SL49130549-203045 + Details
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- Definition Amount of the cumulative effect on retained earnings net of related income tax effect. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=64853466&loc=d3e22663-107794 + Details
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- Definition Losses recognized in the current period on contracts which are expected to generate losses, which are probable and can be reasonably estimated, in a future period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14326-108349 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.2) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 + Details
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- Definition Amount of transaction price allocated to performance obligation that has not been recognized as revenue. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 270 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=84173487&loc=SL51747714-108306 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 13 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=82913847&loc=SL49130556-203045 + Details
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