Borrowings - Breakdown of FHLB Advances and Other Borrowings Outstanding (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Federal Home Loan Bank, Advances, Branch of FHLB Bank
Federal home loan bank, advances, maturities summary, due in next twelve months	$ 4,165	$ 3,244
FHLB, current	$ 0	$ 50
FHLB, interest rate	1.45%	1.53%
FHLB, non-current	$ 650	$ 150
Total	4,815	3,394
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 twelve months	$ 3,695	$ 2,993
FHLB, interest rate	1.61%	2.52%
Other short-term borrowings
Federal Home Loan Bank, Advances, Branch of FHLB Bank
Federal home loan bank, advances, maturities summary, due in next twelve months	$ 470	$ 251
FHLB, interest rate	1.64%	2.87%

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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The current portion of Federal Home Loan Bank borrowings initially due beyond one year or beyond the normal operating cycle if longer.

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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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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 fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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