Segment Reporting - Financial Results by Reportable Segment Reconciled to Consolidated Income Before Income Taxes and Total Assets by Reportable Segment Reconciled to Consolidated Total Assets (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012
REVENUES
Net servicing revenue and fees	$ 218,731	$ 89,344	$ 613,046	$ 267,747
Net gains on sales of loans	153,710		468,104
Interest income on loans	35,702	37,964	109,396	117,697
Net fair value gains on reverse loans and related HMBS obligations	30,476		93,995
Insurance revenue	28,896	17,335	64,480	54,100
Other revenues	21,652	4,430	50,639	13,259
Total revenues	489,167	149,073	1,399,660	452,803
EXPENSES
Interest expense	75,017	43,986	197,449	134,347
Depreciation and amortization	17,757	12,087	51,704	35,920
Provision for loan losses	545	4,596	2,366	8,122
Other expenses, net	281,537	80,952	749,130	263,478
Total expenses	374,856	141,621	1,000,649	441,867
OTHER GAINS (LOSSES)
Other net fair value gains (losses)	6,507	3,123	6,902	8,674
Income (loss) before income taxes	120,818	10,575	405,913	19,610
Total assets	16,807,299	4,005,923	16,807,299	4,005,923	10,978,177
Operating Segments [Member] | Servicing [Member]
REVENUES
Net servicing revenue and fees	206,602	84,795	576,161	256,064
Other revenues	1,848	462	2,767	2,281
Total revenues	208,450	85,257	578,928	258,345
EXPENSES
Interest expense	8,629	1,085	16,205	3,808
Depreciation and amortization	9,402	8,677	27,704	25,916
Other expenses, net	121,269	57,095	330,231	194,341
Total expenses	139,300	66,857	374,140	224,065
OTHER GAINS (LOSSES)
Other net fair value gains (losses)	(197)	(251)	(621)	(783)
Income (loss) before income taxes	68,953	18,149	204,167	33,497
Total assets	3,865,509	1,409,809	3,865,509	1,409,809
Operating Segments [Member] | Reverse Mortgage [Member]
REVENUES
Net servicing revenue and fees	7,023		20,395
Net gains on sales of loans			4,633
Net fair value gains on reverse loans and related HMBS obligations	30,476		93,995
Other revenues	4,214		9,525
Total revenues	41,713		128,548
EXPENSES
Interest expense	1,306		7,001
Depreciation and amortization	2,856		8,270
Other expenses, net	35,326		108,780
Total expenses	39,488		124,051
OTHER GAINS (LOSSES)
Income (loss) before income taxes	2,225		4,497
Total assets	8,606,070		8,606,070
Operating Segments [Member] | Originations [Member]
REVENUES
Net gains on sales of loans	153,710		463,471
Other revenues	13,669	1,419	31,193	3,517
Total revenues	167,379	1,419	494,664	3,517
EXPENSES
Interest expense	10,359		19,665
Depreciation and amortization	2,783	30	7,149	55
Other expenses, net	102,474	2,055	235,949	4,150
Total expenses	115,616	2,085	262,763	4,205
OTHER GAINS (LOSSES)
Income (loss) before income taxes	51,763	(666)	231,901	(688)
Total assets	1,935,562	2,920	1,935,562	2,920
Operating Segments [Member] | Asset Receivables Management [Member]
REVENUES
Net servicing revenue and fees	9,836	9,755	31,028	27,584
Other revenues	41		174
Total revenues	9,877	9,755	31,202	27,584
EXPENSES
Depreciation and amortization	1,497	2,004	4,867	5,901
Other expenses, net	5,289	5,765	17,041	16,473
Total expenses	6,786	7,769	21,908	22,374
OTHER GAINS (LOSSES)
Income (loss) before income taxes	3,091	1,986	9,294	5,210
Total assets	52,655	57,135	52,655	57,135
Operating Segments [Member] | Insurance [Member]
REVENUES
Insurance revenue	28,896	17,335	64,480	54,100
Other revenues	4	88	17	577
Total revenues	28,900	17,423	64,497	54,677
EXPENSES
Depreciation and amortization	1,210	1,369	3,692	4,026
Other expenses, net	8,483	8,000	24,925	26,123
Total expenses	9,693	9,369	28,617	30,149
OTHER GAINS (LOSSES)
Income (loss) before income taxes	19,207	8,054	35,880	24,528
Total assets	230,240	177,362	230,240	177,362
Operating Segments [Member] | Loans and Residuals [Member]
REVENUES
Interest income on loans	35,702	37,964	109,396	117,697
Other revenues	3		7
Total revenues	35,705	37,964	109,403	117,697
EXPENSES
Interest expense	21,376	23,081	65,472	70,484
Provision for loan losses	545	4,596	2,366	8,122
Other expenses, net	6,520	6,294	15,342	21,082
Total expenses	28,441	33,971	83,180	99,688
OTHER GAINS (LOSSES)
Other net fair value gains (losses)	102	482	506	305
Income (loss) before income taxes	7,366	4,475	26,729	18,314
Total assets	1,521,792	1,629,687	1,521,792	1,629,687
Operating Segments [Member] | Other [Member]
REVENUES
Other revenues	1,873	2,461	6,995	6,884
Total revenues	1,873	2,461	6,995	6,884
EXPENSES
Interest expense	33,347	19,820	89,106	60,055
Depreciation and amortization	9	7	22	22
Other expenses, net	6,906	6,949	31,439	17,210
Total expenses	40,262	26,776	120,567	77,287
OTHER GAINS (LOSSES)
Other net fair value gains (losses)	6,602	2,892	7,017	9,152
Income (loss) before income taxes	(31,787)	(21,423)	(106,555)	(61,251)
Total assets	1,553,113	1,062,132	1,553,113	1,062,132
Eliminations [Member]
REVENUES
Net servicing revenue and fees	(4,730)	(5,206)	(14,538)	(15,901)
Other revenues			(39)
Total revenues	(4,730)	(5,206)	(14,577)	(15,901)
EXPENSES
Other expenses, net	(4,730)	(5,206)	(14,577)	(15,901)
Total expenses	(4,730)	(5,206)	(14,577)	(15,901)
OTHER GAINS (LOSSES)
Total assets	$ (957,642)	$ (333,122)	$ (957,642)	$ (333,122)