Deposits Deposits (Schedule of Maturities of Domestic Deposits of One Hundred Thousand or More) (Details) - Domestic certificates of deposit and other deposits - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Three Months or Less	$ 355	$ 510
Over three months to six months	207	322
Over six months to twelve months	319	449
Over twelve months	130	230
Total	$ 1,011	$ 1,511

- Definition

Amount of time deposit liabilities, including certificates of deposit, in denominations of $100,000 or more, maturing after twelve months from the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Industry Guide
-Number 3
-Section V
-Paragraph D-E

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- Definition

Amount of time deposit liabilities, including certificates of deposit, in denominations of $100,000 or more, maturing within six to twelve months after the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Industry Guide
-Number 3
-Section V
-Paragraph D-E

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- Definition

Amount of time deposit liabilities, including certificates of deposit, in denominations of $100,000 or more, maturing within three months or fewer from the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Industry Guide
-Number 3
-Section V
-Paragraph D-E

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- Definition

Amount of time deposit liabilities, including certificates of deposit, in denominations of $100,000 or more, maturing within three to six months after the balance sheet date.

+ References

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-Publisher SEC
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-Number 3
-Section V
-Paragraph D-E

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- Definition

Amount of time deposit liabilities, including certificates of deposit, in denominations of $100,000 or more.

+ References

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-Name Industry Guide
-Number 3
-Section V
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