Segments and Related Information (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013 item	Sep. 30, 2012	Dec. 31, 2012
Segments and Related Information
Number of operating segments			2
Revenues:
Net gains on mortgage loans held for sale at fair value	$ 25,949,000	$ 39,760,000	$ 108,560,000	$ 68,487,000
Loan origination fees	6,280,000	2,752,000	18,260,000	5,439,000
Net servicing income	21,399,000	6,112,000	59,510,000	25,346,000
Management fees	10,540,000	6,114,000	29,375,000	15,163,000
Net interest income:
Interest income	5,093,000	1,914,000	11,310,000	4,491,000
Interest expense	(4,156,000)	(2,042,000)	(11,686,000)	(4,226,000)
Net interest income (expense)	937,000	(128,000)	(376,000)	265,000
Other	950,000	1,009,000	1,774,000	2,515,000
Total net revenue	87,194,000	76,232,000	296,139,000	155,567,000
Expenses:
Compensation	35,830,000	31,856,000	113,850,000	77,756,000
Other	16,447,000	6,513,000	41,850,000	14,909,000
Total expenses	52,277,000	38,369,000	155,700,000	92,664,000
Income before provision for income taxes	34,917,000	37,863,000	140,439,000	62,903,000
Segment assets at period end	1,254,384,000	727,262,000	1,254,384,000	727,262,000	832,163,000
PMT
Revenues:
Fulfillment fees from affiliate	18,327,000	17,258,000	68,625,000	31,097,000
Management fees	8,539,000	3,672,000	23,486,000	7,964,000
Net interest income:
Other	165,000	314,000	(68,000)	630,000
Investment Funds
Revenues:
Management fees	2,001,000	2,442,000	5,889,000	7,199,000
Carried Interest from Investment Funds	2,812,000	3,355,000	10,411,000	7,254,000
Operating segment | Investment Funds
Revenues:
Carried Interest from Investment Funds	2,812,000	3,355,000	10,411,000	7,255,000
Operating segment | Mortgage banking
Revenues:
Net gains on mortgage loans held for sale at fair value	25,949,000	39,760,000	108,560,000	68,487,000
Loan origination fees	6,280,000	2,752,000	18,260,000	5,439,000
Net servicing income	21,399,000	6,112,000	59,510,000	25,346,000
Net interest income:
Interest income	5,089,000	1,913,000	11,296,000	4,488,000
Interest expense	(4,156,000)	(2,042,000)	(11,686,000)	(4,226,000)
Net interest income (expense)	933,000	(129,000)	(390,000)	262,000
Other	(22,000)	1,000	(22,000)	1,000
Total net revenue	72,866,000	65,754,000	254,543,000	130,632,000
Expenses:
Compensation	33,969,000	29,089,000	106,584,000	71,541,000
Other	16,240,000	6,375,000	41,354,000	14,443,000
Total expenses	50,209,000	35,464,000	147,938,000	85,984,000
Income before provision for income taxes	22,657,000	30,290,000	106,605,000	44,648,000
Segment assets at period end	1,208,156,000	709,733,000	1,208,156,000	709,733,000
Operating segment | Mortgage banking | PMT
Revenues:
Fulfillment fees from affiliate	18,327,000	17,258,000	68,625,000	31,097,000
Operating segment | Investment management
Revenues:
Management fees	10,540,000	6,114,000	29,375,000	15,163,000
Net interest income:
Interest income	4,000	1,000	14,000	3,000
Net interest income (expense)	4,000	1,000	14,000	3,000
Other	972,000	1,008,000	1,796,000	2,514,000
Total net revenue	14,328,000	10,478,000	41,596,000	24,935,000
Expenses:
Compensation	1,861,000	2,767,000	7,266,000	6,214,000
Other	207,000	138,000	496,000	466,000
Total expenses	2,068,000	2,905,000	7,762,000	6,680,000
Income before provision for income taxes	12,260,000	7,573,000	33,834,000	18,255,000
Segment assets at period end	46,228,000	17,529,000	46,228,000	17,529,000
Operating segment | Investment management | Investment Funds
Revenues:
Carried Interest from Investment Funds	$ 2,812,000	$ 3,355,000	$ 10,411,000	$ 7,255,000