Customer Deposits (Details 2) $ in Millions	Mar. 31, 2020 USD ($)
Time Deposits By Maturity
2020	$ 4,191
2021	3,235
2022	2,747
2023	508
2024	267
After 5 years	140
Total	11,088
United States [Member]
Time Deposits By Maturity
2020	4,180
2021	3,233
2022	2,747
2023	508
2024	267
After 5 years	140
Total	11,075
Non-US [Member]
Time Deposits By Maturity
2020	11
2021	2
2022	0
2023	0
2024	0
After 5 years	0
Total	$ 13

Amount of time deposits maturing after the fifth fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of time deposits maturing in the remainder of the fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of time deposits maturing in the fifth fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of time deposits maturing in the fourth fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of time deposits maturing in the third fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of time deposits maturing in the second fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of time deposit liabilities, including certificates of deposit.

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