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Accumulated Other Comprehensive Income (Changes In The Components Of AOCI) (Detail) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Beginning balance | $ (2) | $ (156) | $ (19)
Other comprehensive income (loss) before reclassifications | 130 | 114 |
Amounts reclassified from AOCI | (13) | 40 |
Total other comprehensive income (loss) | 117 | 154 | 30
Ending balance | 115 | (2) | (156)
Unrealized gains (losses) on AFS, net [Member] |  |  |
Beginning balance | 112 | (39) | (10)
Other comprehensive income (loss) before reclassifications | 83 | 139 |
Amounts reclassified from AOCI | (19) | 12 |
Total other comprehensive income (loss) | 64 | 151 | (24)
Ending balance | 176 | 112 | (39)
Unrealized gains (losses) on AFS, net [Member] | ASU 2016-01 |  |  |
ASU transition adjustment |  |  | (2)
Unrealized gains (losses) on AFS, net [Member] | ASU 2018-02 |  |  |
ASU transition adjustment |  |  | (3)
Foreign currency translation, net [Member] |  |  |
Beginning balance | (7) | (7) | (9)
Other comprehensive income (loss) before reclassifications | (3) | 0 |
Amounts reclassified from AOCI | 0 | 0 |
Total other comprehensive income (loss) | (3) | 0 | 2
Ending balance | (10) | (7) | (7)
Foreign currency translation, net [Member] | ASU 2016-01 |  |  |
ASU transition adjustment |  |  | 0
Foreign currency translation, net [Member] | ASU 2018-02 |  |  |
ASU transition adjustment |  |  | 0
Instrument-specific credit risk of liabilities measured at fair value, net [Member] |  |  |
Beginning balance | (107) | (110) | 0
Other comprehensive income (loss) before reclassifications | 50 | (25) |
Amounts reclassified from AOCI | 6 | 28 |
Total other comprehensive income (loss) | 56 | 3 | 52
Ending balance | (51) | (107) | (110)
Instrument-specific credit risk of liabilities measured at fair value, net [Member] | ASU 2016-01 |  |  |
ASU transition adjustment |  |  | (162)
Instrument-specific credit risk of liabilities measured at fair value, net [Member] | ASU 2018-02 |  |  |
ASU transition adjustment |  |  | 0
AOCI Attributable to Parent [Member] |  |  |
Total other comprehensive income (loss) | 117 | 154 | 30
AOCI Attributable to Parent [Member] | ASU 2016-01 |  |  |
ASU transition adjustment | 0 | 0 | (164)
AOCI Attributable to Parent [Member] | ASU 2018-02 |  |  |
ASU transition adjustment | $ 0 | $ 0 | $ (3)

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