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Revenue Recognition - Additional Information (Detail1) - USD ($) $ in Billions | Dec. 31, 2018 | Jan. 01, 2018
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Revenue From Contract With Customer [Line Items] |  |
Unfulfilled performance obligation |  | $ 1.1
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2019-01-01 |  |
Revenue From Contract With Customer [Line Items] |  |
Unfulfilled performance obligation | $ 1.4 |
Expected period to satisfy performance obligations | 1 year |

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- Definition Revenue from contract with customer. + References No definition available. + 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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- Definition Period in which remaining performance obligation is expected to be recognized as revenue, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + 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 (b)(1) -URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130556-203045 + Details
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- Details
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