Fair Value Election and Measurement Level 3 Significant Unobservable Input Assumptions (Details) - USD ($) $ in Millions		3 Months Ended		12 Months Ended
		Mar. 31, 2016		Dec. 31, 2015
level 3 fair value assumptions [Line Items]
Trading assets	[1]	$ 7,050		$ 6,119
Available-for-sale Securities		28,188		27,825
Loans Held-for-sale, Fair Value Disclosure		1,593		1,494
Loans Receivable, Fair Value Disclosure		255		257
Servicing Asset at Fair Value, Amount		1,182		1,307
Other Liabilities, Fair Value Disclosure	[2]			23
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
level 3 fair value assumptions [Line Items]
Trading assets		37		110
Available-for-sale Securities		580		556
Loans Receivable, Fair Value Disclosure		255		257
Servicing Asset at Fair Value, Amount		1,182		1,307
Other Liabilities, Fair Value Disclosure	[2]			23
Fair Value, Measurements, Recurring [Member] | Market Approach Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member]
level 3 fair value assumptions [Line Items]
Other Assets, Fair Value Disclosure		32	[3]	$ 15	[4]
Fair Value, Measurements, Recurring [Member] | Other Liabilities [Member] | Income Approach Valuation Technique [Member] | Minimum [Member] | Fair Value, Inputs, Level 3 [Member]
level 3 fair value assumptions [Line Items]
fair value inputs, loan production volume				0.00%
Fair Value, Measurements, Recurring [Member] | Other Liabilities [Member] | Income Approach Valuation Technique [Member] | Maximum [Member] | Fair Value, Inputs, Level 3 [Member]
level 3 fair value assumptions [Line Items]
fair value inputs, loan production volume				150.00%
Fair Value, Measurements, Recurring [Member] | Other Liabilities [Member] | Income Approach Valuation Technique [Member] | Weighted Average [Member] | Fair Value, Inputs, Level 3 [Member]
level 3 fair value assumptions [Line Items]
fair value inputs, loan production volume				150.00%
Fair Value, Measurements, Recurring [Member] | Other Liabilities [Member] | Income Approach Valuation Technique [Member] | Loan Production Volume [Member] | Fair Value, Inputs, Level 3 [Member]
level 3 fair value assumptions [Line Items]
Other Liabilities, Fair Value Disclosure	[5]			$ 23
Fair Value, Measurements, Recurring [Member] | Debt Securities [Member] | Market Approach Valuation Technique [Member] | Minimum [Member] | Fair Value, Inputs, Level 3 [Member]
level 3 fair value assumptions [Line Items]
Fair Value Inputs, Comparability Adjustments				1.26%
Fair Value, Measurements, Recurring [Member] | Debt Securities [Member] | Market Approach Valuation Technique [Member] | Maximum [Member] | Fair Value, Inputs, Level 3 [Member]
level 3 fair value assumptions [Line Items]
Fair Value Inputs, Comparability Adjustments				4.47%
Fair Value, Measurements, Recurring [Member] | Debt Securities [Member] | Market Approach Valuation Technique [Member] | Weighted Average [Member] | Fair Value, Inputs, Level 3 [Member]
level 3 fair value assumptions [Line Items]
Fair Value Inputs, Comparability Adjustments				2.87%
Fair Value, Measurements, Recurring [Member] | Equity Securities [Member] | Cost Approach Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member]
level 3 fair value assumptions [Line Items]
Available-for-sale Securities		471		$ 440
Fair Value, Measurements, Recurring [Member] | Asset-backed Securities [Member] | Market Approach Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member]
level 3 fair value assumptions [Line Items]
Available-for-sale Securities		11		12
Fair Value, Measurements, Recurring [Member] | Other Debt Obligations [Member] | Market Approach Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member]
level 3 fair value assumptions [Line Items]
Trading assets				89
Fair Value, Measurements, Recurring [Member] | Other Debt Obligations [Member] | Cost Approach Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member]
level 3 fair value assumptions [Line Items]
Available-for-sale Securities		5		5
Fair Value, Measurements, Recurring [Member] | US States and Political Subdivisions Debt Securities [Member] | Cost Approach Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member]
level 3 fair value assumptions [Line Items]
Available-for-sale Securities		5		5
Fair Value, Measurements, Recurring [Member] | Mortgage-backed Securities, Issued by Private Enterprises [Member] | Market Approach Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member]
level 3 fair value assumptions [Line Items]
Available-for-sale Securities		88		94
Fair Value, Measurements, Recurring [Member] | Residential Mortgage, Loans Held For Sale [Member] | Income Approach Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member]
level 3 fair value assumptions [Line Items]
Loans Held-for-sale, Fair Value Disclosure		$ 4		$ 5
Fair Value, Measurements, Recurring [Member] | Residential Mortgage, Loans Held For Sale [Member] | Income Approach Valuation Technique [Member] | Minimum [Member] | Fair Value, Inputs, Level 3 [Member]
level 3 fair value assumptions [Line Items]
Fair Value Inputs, Option Adjusted Spread		1.04%		1.04%
Fair Value Inputs, Prepayment Rate		2.00%		2.00%
Fair Value Inputs, Probability of Default		0.00%		0.00%
Fair Value, Measurements, Recurring [Member] | Residential Mortgage, Loans Held For Sale [Member] | Income Approach Valuation Technique [Member] | Maximum [Member] | Fair Value, Inputs, Level 3 [Member]
level 3 fair value assumptions [Line Items]
Fair Value Inputs, Option Adjusted Spread		1.97%		1.97%
Fair Value Inputs, Prepayment Rate		21.00%		17.00%
Fair Value Inputs, Probability of Default		2.00%		2.00%
Fair Value, Measurements, Recurring [Member] | Residential Mortgage, Loans Held For Sale [Member] | Income Approach Valuation Technique [Member] | Weighted Average [Member] | Fair Value, Inputs, Level 3 [Member]
level 3 fair value assumptions [Line Items]
Fair Value Inputs, Option Adjusted Spread		1.28%		1.25%
Fair Value Inputs, Prepayment Rate		11.00%		8.00%
Fair Value Inputs, Probability of Default		0.60%		0.50%
Fair Value, Measurements, Recurring [Member] | Loans Held For Investment [Member] | Market Approach Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member]
level 3 fair value assumptions [Line Items]
Loans Receivable, Fair Value Disclosure		$ 7		$ 6
Fair Value, Measurements, Recurring [Member] | Loans Held For Investment [Member] | Income Approach Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member]
level 3 fair value assumptions [Line Items]
Loans Receivable, Fair Value Disclosure		$ 248		$ 251
Fair Value, Measurements, Recurring [Member] | Loans Held For Investment [Member] | Income Approach Valuation Technique [Member] | Minimum [Member] | Fair Value, Inputs, Level 3 [Member]
level 3 fair value assumptions [Line Items]
Fair Value Inputs, Option Adjusted Spread		0.62%		0.00%
Fair Value Inputs, Prepayment Rate		3.00%		5.00%
Fair Value Inputs, Probability of Default		0.00%		0.00%
Fair Value, Measurements, Recurring [Member] | Loans Held For Investment [Member] | Income Approach Valuation Technique [Member] | Maximum [Member] | Fair Value, Inputs, Level 3 [Member]
level 3 fair value assumptions [Line Items]
Fair Value Inputs, Option Adjusted Spread		7.84%		7.84%
Fair Value Inputs, Prepayment Rate		38.00%		36.00%
Fair Value Inputs, Probability of Default		5.00%		5.00%
Fair Value, Measurements, Recurring [Member] | Loans Held For Investment [Member] | Income Approach Valuation Technique [Member] | Weighted Average [Member] | Fair Value, Inputs, Level 3 [Member]
level 3 fair value assumptions [Line Items]
Fair Value Inputs, Option Adjusted Spread		1.98%		1.93%
Fair Value Inputs, Prepayment Rate		15.00%		14.00%
Fair Value Inputs, Probability of Default		1.80%		1.70%
Fair Value, Measurements, Recurring [Member] | Mortgage Servicing Rights [Member] | Income Approach Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member]
level 3 fair value assumptions [Line Items]
Servicing Asset at Fair Value, Amount		$ 1,182		$ 1,307
Fair Value, Measurements, Recurring [Member] | Mortgage Servicing Rights [Member] | Income Approach Valuation Technique [Member] | Minimum [Member] | Fair Value, Inputs, Level 3 [Member]
level 3 fair value assumptions [Line Items]
Fair Value Inputs, Option Adjusted Spread		(5.00%)		(5.00%)
Fair Value Inputs, Prepayment Rate		2.00%		2.00%
Fair Value, Measurements, Recurring [Member] | Mortgage Servicing Rights [Member] | Income Approach Valuation Technique [Member] | Maximum [Member] | Fair Value, Inputs, Level 3 [Member]
level 3 fair value assumptions [Line Items]
Fair Value Inputs, Option Adjusted Spread		86.00%		110.00%
Fair Value Inputs, Prepayment Rate		20.00%		21.00%
Fair Value, Measurements, Recurring [Member] | Mortgage Servicing Rights [Member] | Income Approach Valuation Technique [Member] | Weighted Average [Member] | Fair Value, Inputs, Level 3 [Member]
level 3 fair value assumptions [Line Items]
Fair Value Inputs, Option Adjusted Spread		8.00%		8.00%
Fair Value Inputs, Prepayment Rate		13.00%		10.00%
Fair Value, Measurements, Recurring [Member] | Other Assets [Member] | Market Approach Valuation Technique [Member] | Minimum [Member] | Fair Value, Inputs, Level 3 [Member]
level 3 fair value assumptions [Line Items]
Fair Value Inputs, Pull Through Rate		41.00%		24.00%
Fair Value Inputs, Msr Value		0.23%		0.29%
Fair Value, Measurements, Recurring [Member] | Other Assets [Member] | Market Approach Valuation Technique [Member] | Maximum [Member] | Fair Value, Inputs, Level 3 [Member]
level 3 fair value assumptions [Line Items]
Fair Value Inputs, Pull Through Rate		100.00%		100.00%
Fair Value Inputs, Msr Value		1.91%		2.10%
Fair Value, Measurements, Recurring [Member] | Other Assets [Member] | Market Approach Valuation Technique [Member] | Weighted Average [Member] | Fair Value, Inputs, Level 3 [Member]
level 3 fair value assumptions [Line Items]
Fair Value Inputs, Pull Through Rate		75.00%		79.00%
Fair Value Inputs, Msr Value		0.96%		1.03%

[1] Includes trading securities pledged as collateral where counterparties have the right to sell or repledge the collateral of $1,484 million and $1,377 million at March 31, 2016 and December 31, 2015, respectively

[2] Includes contingent consideration obligations related to acquisitions.

[3] Represents the net of IRLC assets and liabilities entered into by the Mortgage Banking segment and includes the derivative liability associated with the Company's sale of Visa shares

[4] Represents the net of IRLC assets and liabilities entered into by the Mortgage Banking segment and includes the derivative liability associated with the Company's sale of Visa shares.

[5] Input assumptions relate to the Company's contingent consideration obligations related to acquisitions. See Note 12, "Guarantees," for additional information.