Variable Interest Entities - Summary of Carrying Amounts of Assets and Liabilities (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
ASSETS
Restricted cash and cash equivalents	$ 811,670	$ 804,803
Residential loans at amortized cost, net	1,361,153	1,394,871
Residential loans at fair value	11,268,401	10,341,375
Receivables at fair value	288,829	319,195
Servicer and protective advances net (includes $79,972 and $52,238 in allowance for uncollectible advances at June 30, 2014 and December 31, 2013, respectively)	1,595,950	1,381,434
Other assets	276,489	413,076
Total assets	18,385,950	17,387,529
Liabilities
Payables and accrued liabilities	622,282	494,139
Servicing advance liabilities	1,040,441	971,286
Mortgage-backed debt	1,803,470	1,887,862
Total liabilities	17,200,761	16,220,513
VIE Primary Beneficiary [Member]
ASSETS
Restricted cash and cash equivalents	71,125	59,080
Residential loans at amortized cost, net	1,339,634	1,377,711
Residential loans at fair value	557,786	587,265
Receivables at fair value	36,181	43,545
Servicer and protective advances net (includes $79,972 and $52,238 in allowance for uncollectible advances at June 30, 2014 and December 31, 2013, respectively)	102,927	75,481
Other assets	45,496	56,254
Total assets	2,153,149	2,199,336
Liabilities
Payables and accrued liabilities	7,907	8,472
Servicing advance liabilities	101,323	67,905
Mortgage-backed debt	1,803,470	1,887,862
Total liabilities	1,912,700	1,964,239
Residual Trusts [Member] | VIE Primary Beneficiary [Member]
ASSETS
Restricted cash and cash equivalents	46,571	44,995
Residential loans at amortized cost, net	1,339,634	1,377,711
Residential loans at fair value	0	0
Receivables at fair value	0	0
Servicer and protective advances net (includes $79,972 and $52,238 in allowance for uncollectible advances at June 30, 2014 and December 31, 2013, respectively)	0	0
Other assets	44,186	54,544
Total assets	1,430,391	1,477,250
Liabilities
Payables and accrued liabilities	7,866	8,391
Servicing advance liabilities	0	0
Mortgage-backed debt	1,151,686	1,203,084
Total liabilities	1,159,552	1,211,475
Non-Residual Trusts [Member] | VIE Primary Beneficiary [Member]
ASSETS
Restricted cash and cash equivalents	13,291	13,086
Residential loans at amortized cost, net	0	0
Residential loans at fair value	557,786	587,265
Receivables at fair value	36,181	43,545
Servicer and protective advances net (includes $79,972 and $52,238 in allowance for uncollectible advances at June 30, 2014 and December 31, 2013, respectively)	0	0
Other assets	1,081	1,302
Total assets	608,339	645,198
Liabilities
Payables and accrued liabilities	0	0
Servicing advance liabilities	0	0
Mortgage-backed debt	651,784	684,778
Total liabilities	651,784	684,778
Servicer and Protective Advance Financing [Member] | VIE Primary Beneficiary [Member]
ASSETS
Restricted cash and cash equivalents	11,263	999
Residential loans at amortized cost, net	0	0
Residential loans at fair value	0	0
Receivables at fair value	0	0
Servicer and protective advances net (includes $79,972 and $52,238 in allowance for uncollectible advances at June 30, 2014 and December 31, 2013, respectively)	102,927	75,481
Other assets	229	408
Total assets	114,419	76,888
Liabilities
Payables and accrued liabilities	41	81
Servicing advance liabilities	101,323	67,905
Mortgage-backed debt	0	0
Total liabilities	$ 101,364	$ 67,986