Servicing of Residential Loans - Schedule of Total Servicing Portfolio (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014 Accounts	Dec. 31, 2013 Accounts
Servicing Portfolio [Line Items]
Total servicing portfolio, Number of Accounts	2,336,565	2,051,796
Total servicing portfolio, Unpaid Principal Balance	$ 252,080,666	$ 217,961,136
Third-party Investors [Member]
Servicing Portfolio [Line Items]
Total servicing portfolio, Number of Accounts	2,221,447	1,939,109
Total servicing portfolio, Unpaid Principal Balance	240,030,221	206,518,774
Third-party Investors [Member] | Capitalized Servicing Rights [Member]
Servicing Portfolio [Line Items]
Total servicing portfolio, Number of Accounts	1,561,604	1,310,357
Total servicing portfolio, Unpaid Principal Balance	176,305,631	146,143,213
Third-party Investors [Member] | Capitalized Sub-servicing [Member]
Servicing Portfolio [Line Items]
Total servicing portfolio, Number of Accounts	217,692	235,112
Total servicing portfolio, Unpaid Principal Balance	11,996,994	13,369,236
Third-party Investors [Member] | Sub-servicing [Member]
Servicing Portfolio [Line Items]
Total servicing portfolio, Number of Accounts	442,151	393,640
Total servicing portfolio, Unpaid Principal Balance	51,727,596	47,006,325
On-balance Sheet [Member] | Residential Loans and Real Estate Owned [Member]
Servicing Portfolio [Line Items]
Total servicing portfolio, Number of Accounts	115,118	112,687
Total servicing portfolio, Unpaid Principal Balance	$ 12,050,445	$ 11,442,362