Intangible Assets - Intangible Assets Subject to Amortization (Details) - USD ($) $ in Millions  | 
Mar. 31, 2021  | 
Dec. 31, 2020  | 
|---|---|---|
| Intangible Assets | 听 | 听 | 
| Gross carrying amount | $ 8,838 | $ 8,786 | 
| Accumulated amortization | (3,606) | (3,408) | 
| Net carrying amount | 5,232 | 5,378 | 
| FIA Agreement | 听 | 听 | 
| Intangible Assets | 听 | 听 | 
| Gross carrying amount | 3,630 | 3,630 | 
| Accumulated amortization | (791) | (742) | 
| Net carrying amount | 2,839 | 2,888 | 
| Customer relationships | 听 | 听 | 
| Intangible Assets | 听 | 听 | 
| Gross carrying amount | 3,053 | 3,053 | 
| Accumulated amortization | (1,461) | (1,389) | 
| Net carrying amount | 1,592 | 1,664 | 
| Licensing agreements | 听 | 听 | 
| Intangible Assets | 听 | 听 | 
| Gross carrying amount | 356 | 355 | 
| Accumulated amortization | (226) | (221) | 
| Net carrying amount | 130 | 134 | 
| Other | 听 | 听 | 
| Intangible Assets | 听 | 听 | 
| Gross carrying amount | 1,799 | 1,748 | 
| Accumulated amortization | (1,128) | (1,056) | 
| Net carrying amount | $ 671 | $ 692 | 
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- Definition Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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- Definition Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available. 
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- Definition Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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