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Revenue from contracts with customers Contract balances (Details 2) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2018 | Sep. 30, 2018 | Dec. 31, 2017
Revenue from Contract with Customer [Abstract] |  |  |
Contract assets | $ 142,376 | $ 142,376 | $ 109,540
Change in contract assets |  | 32,836 |
Contract liabilities - current | (98,470) | (98,470) | (84,123)
Change in contract liabilities - current |  | (14,347) |
Contract liabilities - noncurrent | (399) | (399) | 0
Change in contract liabilities - noncurrent |  | (399) |
Net contract assets | 43,507 | 43,507 | $ 25,417
Change in net contract assets |  | 18,090 |
Amounts included in contract liability at the beginning of the period | 10,300 | 79,200 |
Amounts from performance obligations satisfied in prior periods | $ (8,700) | $ (3,700) |

X
- Definition Amount of increase (decrease) in current contract assets, net + References No definition available. + Details
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X
- Definition Total of net contract assets and liabilities + 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 increase (decrease) in current contract liabilities + References No definition available. + Details
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- Definition Amount of increase (decrease) in noncurrent contract liabilities + References No definition available. + Details
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X
- 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 -Topic 606 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=82913815&loc=SL49130531-203044 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130549-203045 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -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 + Details
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X
- 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 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=82913815&loc=SL49130532-203044 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=82913815&loc=SL49130531-203044 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130549-203045 + Details
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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 noncurrent. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130549-203045 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=82913815&loc=SL49130532-203044 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=82913815&loc=SL49130531-203044 + Details
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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 Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130549-203045 + 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/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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