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Revenue Recognition - Additional Information (Detail) - USD ($) | 6 Months Ended
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Jun. 30, 2018 | Jun. 30, 2017
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |  |
Net revenue recognized from performance obligations | $ 47,000,000 |
Remaining performance obligations | 2,610,000,000 |
Impairment losses on contract assets | 0 | $ 0
Advance payments and deferred revenue | 240,000,000 |
2018 [Member] |  |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |  |
Remaining performance obligations | 775,000,000 |
2019 and Thereafter [Member] |  |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |  |
Remaining performance obligations | $ 1,835,000,000 |

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- Definition Amount of impairment loss for asset recognized from cost incurred to obtain or fulfill contract with customer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 340 -SubTopic 40 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=68051541&loc=SL49131252-203054 + 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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- 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/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 13 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130556-203045 + Details
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