Goodwill and Other Intangible Assets - Summary of the Key Characteristics, Inputs, and Economic Assumptions Used to Estimate the Fair Value of the Company's MSRs (Detail) (USD $)	3 Months Ended		6 Months Ended			6 Months Ended	12 Months Ended	3 Months Ended			6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013	Jun. 30, 2014 Mortgage Servicing Rights, Fair Value [Member]	Dec. 31, 2013 Mortgage Servicing Rights, Fair Value [Member]	Jun. 30, 2014 Mortgage Servicing Rights, Fair Value [Member]	Mar. 31, 2014 Mortgage Servicing Rights, Fair Value [Member]	Jun. 30, 2013 Mortgage Servicing Rights, Fair Value [Member]	Jun. 30, 2014 Mortgage Servicing Rights, Fair Value [Member]	Jun. 30, 2013 Mortgage Servicing Rights, Fair Value [Member]	Dec. 31, 2013 Mortgage Servicing Rights, Fair Value [Member]	Dec. 31, 2012 Mortgage Servicing Rights, Fair Value [Member]
Principal Amount Sold on Loans Serviced for Third Parties											$ 439,000,000	$ 632,000,000
Bank Servicing Fees	45,000,000	1,000,000	99,000,000	39,000,000				81,000,000	160,000,000	77,000,000		153,000,000
Servicing Asset at Fair Value, Amount	1,259,000,000		1,259,000,000		1,300,000,000			1,259,000,000		1,199,000,000	1,259,000,000	1,199,000,000	1,300,000,000	899,000,000
Prepayment rate assumption (annual)						9.00%	8.00%
Decline in fair value from 10% adverse change						45,000,000	38,000,000
Decline in fair value from 20% adverse change						88,000,000	74,000,000
Discount rate (annual)						11.00%	12.00%
Decline in fair value from 10% adverse change						59,000,000	66,000,000
Decline in fair value from 20% adverse change						114,000,000	126,000,000
Weighted-average life (in years)						7 years 0 months	7 years 8 months
Weighted-average coupon						4.30%	4.40%
Principal Amount Outstanding Underlying MSRs Purchased								5,900,000,000
Principal Amount Outstanding Underlying MSRs Transferred								$ 460,000,000