Fair Value Measurements (Fair Values of Assets and Liabilities (Significant Unobservable Level 3 Inputs Nonrecurring Basis)) (Detail) - USD ($) $ in Millions	3 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Commercial Loans Held For Sale | Commercial
Quantitative Information About Level 3 Fair Value Measurements
Fair value measurements nonrecurring assets	$ 8	$ 85
Commercial and Industrial Loans | Commercial
Quantitative Information About Level 3 Fair Value Measurements
Fair value measurements nonrecurring assets	354	321
Commercial Mortgage Loans | Commercial
Quantitative Information About Level 3 Fair Value Measurements
Fair value measurements nonrecurring assets	20	58
Commercial construction loans | Commercial
Quantitative Information About Level 3 Fair Value Measurements
Fair value measurements nonrecurring assets		0
Commercial Leases | Commercial
Quantitative Information About Level 3 Fair Value Measurements
Fair value measurements nonrecurring assets	1	0
Servicing Rights
Quantitative Information About Level 3 Fair Value Measurements
Fair value measurements nonrecurring assets		619
OREO Property
Quantitative Information About Level 3 Fair Value Measurements
Fair value measurements nonrecurring assets	20	46
Bank premises and equipment
Quantitative Information About Level 3 Fair Value Measurements
Fair value measurements nonrecurring assets	25	67
Operating lease equipment
Quantitative Information About Level 3 Fair Value Measurements
Fair value measurements nonrecurring assets	$ 56	39
Private Equity Investments
Quantitative Information About Level 3 Fair Value Measurements
Fair value measurements nonrecurring assets		$ 63
Minimum | Residential mortgage loans
Quantitative Information About Level 3 Fair Value Measurements
Interest rate risk factor	(9.20%)	(5.00%)
Credit risk factor	0.00%	0.00%
Minimum | Servicing Rights
Quantitative Information About Level 3 Fair Value Measurements
Prepayment speed	0.80%	0.00%
OAS spread (bps)	4.30%	1.00%
Minimum | Private Equity Investments
Quantitative Information About Level 3 Fair Value Measurements
Liquidity discount		5.00%
Maximum | Residential mortgage loans
Quantitative Information About Level 3 Fair Value Measurements
Interest rate risk factor	14.90%	15.70%
Credit risk factor	46.20%	80.30%
Maximum | Servicing Rights
Quantitative Information About Level 3 Fair Value Measurements
Prepayment speed	98.00%	100.00%
OAS spread (bps)	15.15%	15.15%
Maximum | Private Equity Investments
Quantitative Information About Level 3 Fair Value Measurements
Liquidity discount		37.50%
Weighted average | Commercial Loans Held For Sale
Quantitative Information About Level 3 Fair Value Measurements
Cost to sell		10.00%
Weighted average | Residential mortgage loans
Quantitative Information About Level 3 Fair Value Measurements
Interest rate risk factor	3.20%	5.10%
Credit risk factor	1.00%	1.20%
Weighted average | Private Equity Investments
Quantitative Information About Level 3 Fair Value Measurements
Liquidity discount		12.60%
Weighted average | Fixed | Servicing Rights
Quantitative Information About Level 3 Fair Value Measurements
Prepayment speed	11.80%	14.90%
OAS spread (bps)	5.02%	6.15%
Weighted average | Adjustable | Servicing Rights
Quantitative Information About Level 3 Fair Value Measurements
Prepayment speed	25.20%	27.10%
OAS spread (bps)	7.84%	7.24%