Fair Value of Financial Instruments (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Total realized and unrealized (losses) gains:
Net accretion			$ 23,484	$ 25,064
Total realized and unrealized (losses) gains:
Net accretion			23,484	25,064
Level III
Changes in financial assets classified as Level III
Balance at the beginning of the period		233,456		470,327
Total realized and unrealized (losses) gains:
Net accretion	5,940	5,924	17,846	12,548
Purchases / Originations		95,814		203,433
Sales		(9,425)		(158,177)
Deconsolidations of VIEs			(584,804)
Balance at the end of the period		337,900		337,900
Amount of total (losses) gains included in earnings attributable to assets still held at period end	(4,028,234)		(7,714,797)
Changes in financial instruments classified as Level III
Balance at the beginning of the period	95,764,934		333,153
Acquisition of LNR			89,471,477
Total realized and unrealized (losses) gains:
Included in earnings: Change in fair value	(4,016,254)		(7,712,129)
Included in earnings: Impairment	(52)		(453)
Included in other comprehensive income	5,316		5,352
Net accretion	5,940	5,924	17,846	12,548
Purchases / Originations	481,339		892,137
Sales	(375,204)		(874,323)
Issuances	(8,760)		(8,760)
Cash repayments / receipts	(19,503)		27,475
Transfers into level 3	(83,708)		(460,906)
Transfers out of level 3	483,608		636,291
Consolidations of VIEs	4,290,074		14,784,360
Deconsolidations of VIEs	(153)		(583,943)
Balance at the end of the period	96,527,577		96,527,577
Amount of total (losses) gains included in earnings attributable to assets still held at period end	(4,028,234)		(7,714,797)
VIE liabilities | Level III
Changes in financial liabilities classified as Level III
Balance at the beginning of the period	(2,334,660)
Acquisition of LNR			(1,994,243)
Total realized and unrealized (losses) gains:
Included in earnings: Change in fair value	239,094		333,542
Issuances	(8,760)		(8,760)
Cash repayments / receipts	(5,041)		74,694
Transfers into Level III	(88,806)		(578,319)
Transfers out of Level III	483,608		636,291
Consolidations of VIEs	(69,075)		(247,706)
Deconsolidations of VIEs			861
Balance at the end of the period	(1,783,640)		(1,783,640)
Amount of total (losses) gains included in earnings attributable to assets still held at period end	239,094		333,542
Loans Held-for-sale | Level III
Changes in financial assets classified as Level III
Balance at the beginning of the period	171,176			128,593
Acquisition of LNR			256,502
Total realized and unrealized (losses) gains:
Included in earnings: Change in fair value	25,856		26,315
Purchases / Originations	457,468		848,137
Sales	(375,204)		(851,539)	(132,128)
Cash repayments / receipts	(175)		(294)
Balance at the end of the period	279,121		279,121
Amount of total (losses) gains included in earnings attributable to assets still held at period end	6,011		6,011
RMBS | Level III
Changes in financial assets classified as Level III
Balance at the beginning of the period	319,655		333,153
Total realized and unrealized (losses) gains:
Included in earnings: Change in fair value			2,129
Included in earnings: Impairment	(52)		(453)
Included in other comprehensive income	4,842		2,970
Net accretion	5,940		17,846
Purchases / Originations			20,090
Sales			(12,712)
Cash repayments / receipts	(14,124)		(46,762)
Balance at the end of the period	316,261		316,261
Amount of total (losses) gains included in earnings attributable to assets still held at period end	7,057		21,363
Total realized and unrealized (losses) gains:
Net accretion	5,940		17,846
CMBS | Level III
Changes in financial assets classified as Level III
Balance at the beginning of the period	164,399
Acquisition of LNR			62,432
Total realized and unrealized (losses) gains:
Included in earnings: Change in fair value	4,620		3,452
Included in other comprehensive income	474		2,382
Purchases / Originations	23,871		23,910
Sales			(10,072)
Cash repayments / receipts	(163)		(163)
Transfers into Level III	5,098		117,413
Consolidations of VIEs			(1,208)
Deconsolidations of VIEs	(153)
Balance at the end of the period	198,146		198,146
Amount of total (losses) gains included in earnings attributable to assets still held at period end	5,428		1,854
Domestic Servicing Rights | Level III
Changes in financial assets classified as Level III
Balance at the beginning of the period	159,891
Acquisition of LNR			156,993
Total realized and unrealized (losses) gains:
Included in earnings: Change in fair value	(1,868)		1,030
Balance at the end of the period	158,023		158,023
Amount of total (losses) gains included in earnings attributable to assets still held at period end	(1,868)		1,030
VIE assets | Level III
Changes in financial assets classified as Level III
Balance at the beginning of the period	97,284,473
Acquisition of LNR			90,989,793
Total realized and unrealized (losses) gains:
Included in earnings: Change in fair value	(4,283,956)		(8,078,597)
Consolidations of VIEs	4,359,149		15,033,274
Deconsolidations of VIEs			(584,804)
Balance at the end of the period	97,359,666		97,359,666
Amount of total (losses) gains included in earnings attributable to assets still held at period end	$ (4,283,956)		$ (8,078,597)