Long-Term Debt - Long Term Debt Table (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Mark-to-market adjustment on fair value option long-term debt	$ 36	$ 91
Unamortized discount	(21)	(26)
HSBC acquisition purchase accounting fair value adjustments	19	20
Long-term debt	4,340	9,510
Other Fixed Rate Senior Debt [Member] \| 3.00%-3.99% Other Fixed Rate Senior Debt [Member]
Debt Instrument [Line Items]
Long-term debt, gross	0	88
Other Fixed Rate Senior Debt [Member] \| 4.00%-4.99% Other Fixed Rate Senior Debt Due 2018 [Member]
Debt Instrument [Line Items]
Long-term debt, gross	70	68
Other Fixed Rate Senior Debt [Member] \| 5.00%-5.49% Other Fixed Rate Senior Debt Due 2017-2021 [Member]
Debt Instrument [Line Items]
Long-term debt, gross	1,182	1,211
Other Fixed Rate Senior Debt [Member] \| 5.50%-5.99% Other Fixed Rate Senior Debt Due 2017-2018 [Member]
Debt Instrument [Line Items]
Long-term debt, gross	139	1,999
Other Fixed Rate Senior Debt [Member] \| 6.00%-6.49% Other Fixed Rate Senior Debt Due 2017 [Member]
Debt Instrument [Line Items]
Long-term debt, gross	29	1,369
Other Fixed Rate Senior Debt [Member] \| 7.00%-7.49% Other Fixed Rate Senior Debt Due 2023-2032 [Member]
Debt Instrument [Line Items]
Long-term debt, gross	37	37
Other Fixed Rate Senior Debt [Member] \| 7.50%-7.99 Other Fixed Rate Senior Debt Due 2019-2032 [Member]
Debt Instrument [Line Items]
Long-term debt, gross	237	266
Variable Interest Rate Debt [Member] \| Secured financings – .93% to 3.24%; due 2017 to 2018 [Member]
Debt Instrument [Line Items]
Long-term debt, gross	404	879
Variable Interest Rate Debt [Member] \| Other variable interest rate senior debt – .84% [Member]
Debt Instrument [Line Items]
Long-term debt, gross	$ 0	1,300
Stated percentage	0.84%
Subordinated Debt [Member] \| Subordinated Debt, 6.68% due 2021 [Member]
Debt Instrument [Line Items]
Long-term debt, gross	$ 2,208	$ 2,208
Stated percentage	6.675%
Minimum [Member] \| Other Fixed Rate Senior Debt [Member] \| 3.00%-3.99% Other Fixed Rate Senior Debt [Member]
Debt Instrument [Line Items]
Stated percentage	3.00%
Minimum [Member] \| Other Fixed Rate Senior Debt [Member] \| 4.00%-4.99% Other Fixed Rate Senior Debt Due 2018 [Member]
Debt Instrument [Line Items]
Stated percentage	4.00%
Minimum [Member] \| Other Fixed Rate Senior Debt [Member] \| 5.00%-5.49% Other Fixed Rate Senior Debt Due 2017-2021 [Member]
Debt Instrument [Line Items]
Stated percentage	5.00%
Minimum [Member] \| Other Fixed Rate Senior Debt [Member] \| 5.50%-5.99% Other Fixed Rate Senior Debt Due 2017-2018 [Member]
Debt Instrument [Line Items]
Stated percentage	5.50%
Minimum [Member] \| Other Fixed Rate Senior Debt [Member] \| 6.00%-6.49% Other Fixed Rate Senior Debt Due 2017 [Member]
Debt Instrument [Line Items]
Stated percentage	6.00%
Minimum [Member] \| Other Fixed Rate Senior Debt [Member] \| 7.00%-7.49% Other Fixed Rate Senior Debt Due 2023-2032 [Member]
Debt Instrument [Line Items]
Stated percentage	7.00%
Minimum [Member] \| Other Fixed Rate Senior Debt [Member] \| 7.50%-7.99 Other Fixed Rate Senior Debt Due 2019-2032 [Member]
Debt Instrument [Line Items]
Stated percentage	7.50%
Minimum [Member] \| Variable Interest Rate Debt [Member] \| Secured financings – .93% to 3.24%; due 2017 to 2018 [Member]
Debt Instrument [Line Items]
Stated percentage	0.93%
Maximum [Member] \| Other Fixed Rate Senior Debt [Member] \| 3.00%-3.99% Other Fixed Rate Senior Debt [Member]
Debt Instrument [Line Items]
Stated percentage	3.99%
Maximum [Member] \| Other Fixed Rate Senior Debt [Member] \| 4.00%-4.99% Other Fixed Rate Senior Debt Due 2018 [Member]
Debt Instrument [Line Items]
Stated percentage	4.99%
Maximum [Member] \| Other Fixed Rate Senior Debt [Member] \| 5.00%-5.49% Other Fixed Rate Senior Debt Due 2017-2021 [Member]
Debt Instrument [Line Items]
Stated percentage	5.49%
Maximum [Member] \| Other Fixed Rate Senior Debt [Member] \| 5.50%-5.99% Other Fixed Rate Senior Debt Due 2017-2018 [Member]
Debt Instrument [Line Items]
Stated percentage	5.99%
Maximum [Member] \| Other Fixed Rate Senior Debt [Member] \| 6.00%-6.49% Other Fixed Rate Senior Debt Due 2017 [Member]
Debt Instrument [Line Items]
Stated percentage	6.49%
Maximum [Member] \| Other Fixed Rate Senior Debt [Member] \| 7.00%-7.49% Other Fixed Rate Senior Debt Due 2023-2032 [Member]
Debt Instrument [Line Items]
Stated percentage	7.49%
Maximum [Member] \| Other Fixed Rate Senior Debt [Member] \| 7.50%-7.99 Other Fixed Rate Senior Debt Due 2019-2032 [Member]
Debt Instrument [Line Items]
Stated percentage	7.99%
Maximum [Member] \| Variable Interest Rate Debt [Member] \| Secured financings – .93% to 3.24%; due 2017 to 2018 [Member]
Debt Instrument [Line Items]
Stated percentage	3.24%

Acquisition purchase accounting fair value adjustments.

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- Definition

Debt Instrument, Mark to Market Adjustment, Fair Value

+ References

No definition available.

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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-Subparagraph (SX 210.5-02(22))
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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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- Definition

Amount, after accumulated amortization, of debt discount.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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