Carrying Value of Those Assets Measured at Fair Value on a Non-Recurring Basis (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended		3 Months Ended	6 Months Ended	12 Months Ended							3 Months Ended	12 Months Ended							3 Months Ended	6 Months Ended	12 Months Ended							3 Months Ended			6 Months Ended		12 Months Ended							3 Months Ended	6 Months Ended	12 Months Ended							3 Months Ended		6 Months Ended		12 Months Ended	6 Months Ended	12 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014 Loans Held For Sale [Member] Fair Value, Measurements, Nonrecurring [Member]	Jun. 30, 2014 Loans Held For Sale [Member] Fair Value, Measurements, Nonrecurring [Member]	Dec. 31, 2013 Loans Held For Sale [Member] Fair Value, Measurements, Nonrecurring [Member]	Jun. 30, 2014 Loans Held For Sale [Member] Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 1 [Member]	Dec. 31, 2013 Loans Held For Sale [Member] Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 1 [Member]	Jun. 30, 2014 Loans Held For Sale [Member] Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 2 [Member]	Dec. 31, 2013 Loans Held For Sale [Member] Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 2 [Member]	Jun. 30, 2014 Loans Held For Sale [Member] Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 3 [Member]	Dec. 31, 2013 Loans Held For Sale [Member] Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 3 [Member]	Jun. 30, 2014 Loans Held For Investment [Member] Fair Value, Measurements, Nonrecurring [Member]	Dec. 31, 2013 Loans Held For Investment [Member] Fair Value, Measurements, Nonrecurring [Member]	Jun. 30, 2014 Loans Held For Investment [Member] Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 1 [Member]	Dec. 31, 2013 Loans Held For Investment [Member] Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 1 [Member]	Jun. 30, 2014 Loans Held For Investment [Member] Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 2 [Member]	Dec. 31, 2013 Loans Held For Investment [Member] Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 2 [Member]	Jun. 30, 2014 Loans Held For Investment [Member] Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 3 [Member]	Dec. 31, 2013 Loans Held For Investment [Member] Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 3 [Member]	Jun. 30, 2014 Other Real Estate Owned [Member] Fair Value, Measurements, Nonrecurring [Member]	Jun. 30, 2014 Other Real Estate Owned [Member] Fair Value, Measurements, Nonrecurring [Member]	Dec. 31, 2013 Other Real Estate Owned [Member] Fair Value, Measurements, Nonrecurring [Member]	Jun. 30, 2014 Other Real Estate Owned [Member] Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 1 [Member]	Dec. 31, 2013 Other Real Estate Owned [Member] Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 1 [Member]	Jun. 30, 2014 Other Real Estate Owned [Member] Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 2 [Member]	Dec. 31, 2013 Other Real Estate Owned [Member] Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 2 [Member]	Jun. 30, 2014 Other Real Estate Owned [Member] Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 3 [Member]	Dec. 31, 2013 Other Real Estate Owned [Member] Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 3 [Member]	Jun. 30, 2014 Affordable Housing [Member] Fair Value, Measurements, Nonrecurring [Member]	Mar. 31, 2014 Affordable Housing [Member] Fair Value, Measurements, Nonrecurring [Member]	Jun. 30, 2013 Affordable Housing [Member] Fair Value, Measurements, Nonrecurring [Member]	Jun. 30, 2014 Affordable Housing [Member] Fair Value, Measurements, Nonrecurring [Member]	Jun. 30, 2013 Affordable Housing [Member] Fair Value, Measurements, Nonrecurring [Member]	Dec. 31, 2013 Affordable Housing [Member] Fair Value, Measurements, Nonrecurring [Member]	Jun. 30, 2014 Affordable Housing [Member] Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 1 [Member]	Dec. 31, 2013 Affordable Housing [Member] Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 1 [Member]	Jun. 30, 2014 Affordable Housing [Member] Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 2 [Member]	Dec. 31, 2013 Affordable Housing [Member] Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 2 [Member]	Jun. 30, 2014 Affordable Housing [Member] Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 3 [Member]	Dec. 31, 2013 Affordable Housing [Member] Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 3 [Member]	Jun. 30, 2014 Other Assets [Member] Fair Value, Measurements, Nonrecurring [Member]	Jun. 30, 2014 Other Assets [Member] Fair Value, Measurements, Nonrecurring [Member]	Dec. 31, 2013 Other Assets [Member] Fair Value, Measurements, Nonrecurring [Member]	Jun. 30, 2014 Other Assets [Member] Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 1 [Member]	Dec. 31, 2013 Other Assets [Member] Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 1 [Member]	Jun. 30, 2014 Other Assets [Member] Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 2 [Member]	Dec. 31, 2013 Other Assets [Member] Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 2 [Member]	Jun. 30, 2014 Other Assets [Member] Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 3 [Member]	Dec. 31, 2013 Other Assets [Member] Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 3 [Member]	Jun. 30, 2014 Land [Member] Other Assets [Member] Fair Value, Measurements, Nonrecurring [Member]	Jun. 30, 2013 Land [Member] Other Assets [Member] Fair Value, Measurements, Nonrecurring [Member]	Jun. 30, 2014 Land [Member] Other Assets [Member] Fair Value, Measurements, Nonrecurring [Member]	Jun. 30, 2013 Land [Member] Other Assets [Member] Fair Value, Measurements, Nonrecurring [Member]	Dec. 31, 2013 Nonperforming Financing Receivable [Member] Residential Mortgage, Loans Held For Sale [Member]	Jun. 30, 2014 Nonperforming Financing Receivable [Member] Loans Held For Sale [Member]	Dec. 31, 2013 Nonperforming Financing Receivable [Member] Loans Held For Sale [Member]	May 30, 2014 Nonperforming Financing Receivable [Member] Loans Held For Sale [Member]	Jun. 30, 2013 Nonperforming Residential Mortgages Transferred To Held For Sale During A Prior Period [Member] Loans Held For Sale [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Document Period End Date			Jun. 30, 2014
Net Carrying Value of Loans Held for Sale, Sold																																																									$ 10
Deconsolidation of assets and liabilities of variable interest entity																																																											2
Residential Mortgages Transferred To Held For Sale, Net Of Impairment																																																										22
Loans held for investment sold	534	159	619	662																																																				39
Assets, Fair Value Disclosure					16	16	278	0	0	16	278	0	0	27	75	0	0	0	0	27	75	44	44	49	0	0	3	1	41	48	63			63		7	0	0	0	0	63	7	85	85	171	0	0	79	158	6	13
Asset Impairment Charges					0	(1)	3							0	0							6	8	10							0	36	2	36	2	3							7	13	61							5	0	5	0
Gain (Loss) on Sales of Loans, Net	$ 22	$ 3	$ 31	$ 7																																																								$ 5