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v3.19.3.a.u2

Revenue Recognition - Additional Information (Detail) | 12 Months Ended
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Dec. 31, 2019 USD ($) Customer | Dec. 31, 2018 USD ($) Customer | Dec. 31, 2017 USD ($) Customer
Revenue Remaining Performance Obligation Expected Timing Of Satisfaction [Line Items] |  |  |
Impairment losses on contract assets | $ | $ 0 | $ 0 | $ 0
Customer Concentration Risk [Member] | Revenue [Member] |  |  |
Revenue Remaining Performance Obligation Expected Timing Of Satisfaction [Line Items] |  |  |
Concentration risk, number of customers | Customer | 0 | 0 | 0
Concentration risk, percentage | 10.00% | 10.00% | 10.00%

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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://www.xbrl.org/2003/role/disclosureRef -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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