Borrowings - Breakdown of FHLB Advances and Other Borrowings Outstanding (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Federal Home Loan Bank, Advances, Branch of FHLB Bank
Federal home loan bank, advances, maturities summary, due in next twelve months	$ 3,900	$ 4,165
FHLB, interest rate	1.03%	1.45%
FHLB, non-current	$ 1,200	$ 650
Total	5,100	4,815
Short-term fixed rate term advances
Federal Home Loan Bank, Advances, Branch of FHLB Bank
Federal home loan bank, advances, maturities summary, due in next rolling twelve months	$ 3,415	$ 3,695
FHLB, interest rate	0.20%	1.61%
Other short-term borrowings
Federal Home Loan Bank, Advances, Branch of FHLB Bank
Federal home loan bank, advances, maturities summary, due in next rolling twelve months	$ 485	$ 470
FHLB, interest rate	0.08%	1.64%

Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

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States the interest rate applicable to Federal Home Loan Bank advances outstanding as of the Balance Sheet date.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 470
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Including both current and noncurrent portions, Federal Home Loan Bank borrowings initially due beyond one year or beyond the normal operating cycle if longer.

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Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the next rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of advance from Federal Home Loan Bank (FHLBank) maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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