Fair Value Election and Measurement Level 3 Significant Unobservable Input Assumptions (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		12 Months Ended
	Mar. 31, 2015		Dec. 31, 2014
level 3 fair value assumptions [Line Items]
Trading assets	6,595	[1]	6,202	[1]
Available-for-sale Securities	26,761	[2]	26,770	[2]
Loans Held-for-sale, Fair Value Disclosure	2,077		1,892
Loans Receivable, Fair Value Disclosure	268		272
Servicing Asset at Fair Value, Amount	1,181		1,206
Other Liabilities, Fair Value Disclosure	21	[3]	27	[3]
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
level 3 fair value assumptions [Line Items]
Trading assets	45		25
Available-for-sale Securities	767		946
Loans Receivable, Fair Value Disclosure	268		272
Servicing Asset at Fair Value, Amount	1,181		1,206
Other Liabilities, Fair Value Disclosure	21	[3]	27	[3]
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	37		20
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%		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%		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			1.07%
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	21	[4]	27	[5]
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	616		785
Fair Value, Measurements, Recurring [Member] | Collateralized Debt Obligations [Member] | Market Approach Valuation Technique [Member] | Minimum [Member] | Fair Value, Inputs, Level 3 [Member]
level 3 fair value assumptions [Line Items]
Fair Value Inputs, indicative pricing based on overcollateralization ratio			0
Fair Value Inputs, Estimated Collateral Losses			0.00%
Fair Value, Measurements, Recurring [Member] | Collateralized Debt Obligations [Member] | Market Approach Valuation Technique [Member] | Maximum [Member] | Fair Value, Inputs, Level 3 [Member]
level 3 fair value assumptions [Line Items]
Fair Value Inputs, indicative pricing based on overcollateralization ratio			0
Fair Value Inputs, Estimated Collateral Losses			0.00%
Fair Value, Measurements, Recurring [Member] | Collateralized Debt Obligations [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, indicative pricing based on overcollateralization ratio			0
Fair Value Inputs, Estimated Collateral Losses			0.00%
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	21		21
Fair Value, Measurements, Recurring [Member] | Asset-backed 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, Indicative Pricing			0
Fair Value, Measurements, Recurring [Member] | Asset-backed 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, Indicative Pricing			0
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] | Market Approach Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member]
level 3 fair value assumptions [Line Items]
Available-for-sale Securities	6		12
Fair Value, Measurements, Recurring [Member] | US States and Political Subdivisions 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, Indicative Pricing			0
Fair Value, Measurements, Recurring [Member] | US States and Political Subdivisions 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, Indicative Pricing			0
Fair Value, Measurements, Recurring [Member] | US States and Political Subdivisions 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, Indicative Pricing			0
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	119		123
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		1
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	1.62%		1.45%
Fair Value Inputs, Conditional Prepayment Rate	2.00%		1.00%
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	1.65%		2.25%
Fair Value Inputs, Conditional Prepayment Rate	20.00%		30.00%
Fair Value Inputs, Probability of Default	2.00%		3.00%
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	1.65%		1.57%
Fair Value Inputs, Conditional Prepayment Rate	13.00%		15.00%
Fair Value Inputs, Probability of Default	0.50%		0.75%
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	4		3
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	264		269
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	0.00%		0.00%
Fair Value Inputs, Conditional Prepayment Rate	4.00%		4.00%
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	4.50%		4.50%
Fair Value Inputs, Conditional Prepayment Rate	35.00%		30.00%
Fair Value Inputs, Probability of Default	5.00%		7.00%
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	2.83%		2.86%
Fair Value Inputs, Conditional Prepayment Rate	14.30%		13.75%
Fair Value Inputs, Probability of Default	1.75%		1.75%
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	1,181		1,206
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	(4.07%)
Fair Value Inputs, Conditional Prepayment Rate	2.00%		2.00%
Fair Value Inputs, Discount Rate			(1.00%)
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	39.77%
Fair Value Inputs, Conditional Prepayment Rate	21.00%		47.00%
Fair Value Inputs, Discount Rate			122.00%
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	9.00%
Fair Value Inputs, Conditional Prepayment Rate	11.00%		11.00%
Fair Value Inputs, Discount Rate			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	38.00%		40.00%
Fair Value Inputs, Msr Value	0.38%		0.39%
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	2.17%		2.18%
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	74.00%		75.00%
Fair Value Inputs, Msr Value	1.15%		1.07%

[1] Includes trading securities pledged as collateral where counterparties have the right to sell or repledge the collateral of $1,207 million and $1,316 million at March 31, 2015 and December 31, 2014, respectively

[2] Includes securities AFS pledged as collateral where counterparties have the right to sell or repledge the collateral of $0 million and $369 million at March 31, 2015 and December 31, 2014, respectively.

[3] Includes contingent consideration obligations related to acquisitions.

[4] 4 Not meaningful.

[5] 3