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-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
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-Section 50
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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.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Revenue - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
Revenue - Narrative (Details) - USD ($) $ in Millions	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Disaggregation Of Revenue [Line Items]
Contract with Customer, Performance Obligation Satisfied in Previous Period	$ 5		$ 14
December 31 2019 [Member]
Disaggregation Of Revenue [Line Items]
Contract with Customer, Liability, Revenue Recognized	130		$ 402
March 31 2020 [Member]
Disaggregation Of Revenue [Line Items]
Contract with Customer, Liability, Revenue Recognized	$ 254
Maximum [Member] \| Other [Member]
Disaggregation Of Revenue [Line Items]
Revenue, Percentage of Total Revenue	5.00%	5.00%	5.00%	5.00%