Valuation (Significant Unobservable Inputs Rollforward) (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023 USD ($) $ / shares	Jun. 30, 2022 USD ($)	Jun. 30, 2023 USD ($) $ / shares	Jun. 30, 2022 USD ($)	Dec. 31, 2022 USD ($) $ / shares
Fair Value, Measurements, Recurring
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Total assets	$ 13,586,027		$ 13,586,027		$ 13,357,204
Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Assets, Beginning Balance	12,237,648	$ 3,348,826	12,034,361	$ 2,881,539
Assets, Accreted Discounts/Amortized Premiums	(4,374)	(6,957)	(7,527)	(15,351)
Assets, Realized Gain (Loss)	(10,431)	2,799	(14,245)	10,253
Assets, Change In Net Unrealized Gain/(Loss)	24,115	(152,622)	242,766	(238,400)
Assets, Purchases	897,836	1,057,895	1,747,708	2,229,118
Assets, Sales	909,282	320,222	(1,793,176)	(924,856)
Assets, Transfers into Level 3	32,492	26,331	58,445	38,365
Assets, Transfers out of Level 3	10,723	5,937	(11,051)	(30,555)
Assets, Ending Balance	12,257,281	3,950,113	12,257,281	3,950,113
Liabilities, Begining Balance	(9,695,833)	1,426,542	(9,518,871)	(984,168)
Liabilities, Accreted Discounts/Amortized Premiums	(261)	0	(664)	0
Liabilities, Realized Gain/(Loss)	0	0	0	0
Liabilities, Change In Net Unrealized Gain/(Loss)	(12,425)	74,608	(167,128)	130,249
Liabilities Purchases/Payments	390,832	99,198	701,821	213,953
Liabilities, Sales/Issuance	395,294	398,096	(728,139)	(1,010,866)
Liabilities, Transfers into Level 3	0	0	0	0
Liabilities, Transfers out of Level 3	0	0	0	0
Liabilities, Ending Balance	(9,712,981)	(1,650,832)	(9,712,981)	(1,650,832)
Level 3 | Fair Value, Measurements, Recurring
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Total assets	12,257,281		12,257,281		12,034,361
Level 3 | Non-Agency RMBS
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Total assets	168,609		168,609		132,502
Level 3 | Non-Agency RMBS | Valuation, Income Approach
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Total assets	68,759		68,759		72,671
Level 3 | Non-Agency RMBS | Valuation, Market Approach
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Total assets	$ 99,850		$ 99,850		$ 59,831
Level 3 | Non-Agency RMBS | Measurement Input, Quoted Price | Valuation, Market Approach | Minimum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Securities, measurement input | $ / shares	0.47		0.47		0.45
Level 3 | Non-Agency RMBS | Measurement Input, Quoted Price | Valuation, Market Approach | Maximum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Securities, measurement input | $ / shares	147.30		147.30		159.91
Level 3 | Non-Agency RMBS | Measurement Input, Quoted Price | Valuation, Market Approach | Weighted Average
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Securities, measurement input | $ / shares	77.49		77.49		69.79
Level 3 | Non-Agency RMBS | Measurement Input, Discount Rate | Minimum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Securities, measurement input	0.000		0.000		0.000
Level 3 | Non-Agency RMBS | Measurement Input, Discount Rate | Maximum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Securities, measurement input	1.047		1.047		0.957
Level 3 | Non-Agency RMBS | Measurement Input, Discount Rate | Weighted Average
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Securities, measurement input	0.124		0.124		0.121
Level 3 | Non-Agency RMBS | Measurement Input, Prepayment Rate | Minimum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Securities, measurement input	0.000		0.000		0.000
Level 3 | Non-Agency RMBS | Measurement Input, Prepayment Rate | Maximum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Securities, measurement input	1.000		1.000		1.000
Level 3 | Non-Agency RMBS | Measurement Input, Prepayment Rate | Weighted Average
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Securities, measurement input	0.359		0.359		0.520
Level 3 | Non-Agency RMBS | Measurement Input, Default Rate | Minimum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Securities, measurement input	0.000		0.000		0.000
Level 3 | Non-Agency RMBS | Measurement Input, Default Rate | Maximum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Securities, measurement input	0.986		0.986		0.974
Level 3 | Non-Agency RMBS | Measurement Input, Default Rate | Weighted Average
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Securities, measurement input	0.144		0.144		0.165
Level 3 | CMBS
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Total assets	$ 12,308		$ 12,308		$ 12,649
Level 3 | CMBS | Valuation, Income Approach
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Total assets	0		0		569
Level 3 | CMBS | Valuation, Market Approach
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Total assets	$ 12,308		$ 12,308		$ 12,080
Level 3 | CMBS | Measurement Input, Quoted Price | Valuation, Market Approach | Minimum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Securities, measurement input | $ / shares	5.20		5.20		5.54
Level 3 | CMBS | Measurement Input, Quoted Price | Valuation, Market Approach | Maximum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Securities, measurement input | $ / shares	70.00		70.00		69.07
Level 3 | CMBS | Measurement Input, Quoted Price | Valuation, Market Approach | Weighted Average
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Securities, measurement input | $ / shares	38.55		38.55		38.37
Level 3 | CMBS | Measurement Input, Discount Rate | Minimum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Securities, measurement input	0.115		0.115		0.094
Level 3 | CMBS | Measurement Input, Discount Rate | Maximum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Securities, measurement input	0.194		0.194		0.175
Level 3 | CMBS | Measurement Input, Discount Rate | Weighted Average
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Securities, measurement input	0.167		0.167		0.127
Level 3 | CMBS | Measurement Input, Default Rate | Minimum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Securities, measurement input	0		0		0.012
Level 3 | CMBS | Measurement Input, Default Rate | Maximum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Securities, measurement input	0.490		0.490		0.398
Level 3 | CMBS | Measurement Input, Default Rate | Weighted Average
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Securities, measurement input	0.048		0.048		0.058
Level 3 | CLOs
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Total assets	$ 19,733		$ 19,733		$ 24,598
Level 3 | CLOs | Valuation, Income Approach
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Total assets	3,758		3,758		6,673
Level 3 | CLOs | Valuation, Market Approach
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Total assets	$ 15,975		$ 15,975		$ 17,925
Level 3 | CLOs | Measurement Input, Quoted Price | Valuation, Market Approach | Minimum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Securities, measurement input | $ / shares	30.10		30.10		3.96
Level 3 | CLOs | Measurement Input, Quoted Price | Valuation, Market Approach | Maximum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Securities, measurement input | $ / shares	95.00		95.00		92.00
Level 3 | CLOs | Measurement Input, Quoted Price | Valuation, Market Approach | Weighted Average
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Securities, measurement input | $ / shares	69.72		69.72		57.94
Level 3 | CLOs | Measurement Input, Discount Rate | Minimum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Securities, measurement input	0.127		0.127		0.132
Level 3 | CLOs | Measurement Input, Discount Rate | Maximum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Securities, measurement input	0.657		0.657		0.361
Level 3 | CLOs | Measurement Input, Discount Rate | Weighted Average
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Securities, measurement input	0.249		0.249		0.233
Level 3 | Asset-backed securities, backed by consumer loans | Valuation, Income Approach
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Total assets	$ 77,139		$ 77,139		$ 73,644
Level 3 | Asset-backed securities, backed by consumer loans | Measurement Input, Discount Rate | Minimum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Securities, measurement input	0.078		0.078		0.067
Level 3 | Asset-backed securities, backed by consumer loans | Measurement Input, Discount Rate | Maximum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Securities, measurement input	0.317		0.317		0.279
Level 3 | Asset-backed securities, backed by consumer loans | Measurement Input, Discount Rate | Weighted Average
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Securities, measurement input	0.130		0.130		0.135
Level 3 | Asset-backed securities, backed by consumer loans | Measurement Input, Prepayment Rate | Minimum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Securities, measurement input	0.000		0.000		0.000
Level 3 | Asset-backed securities, backed by consumer loans | Measurement Input, Prepayment Rate | Maximum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Securities, measurement input	0.234		0.234		0.183
Level 3 | Asset-backed securities, backed by consumer loans | Measurement Input, Prepayment Rate | Weighted Average
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Securities, measurement input	0.163		0.163		0.144
Level 3 | Asset-backed securities, backed by consumer loans | Measurement Input, Default Rate | Minimum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Securities, measurement input	0.000		0.000		0.006
Level 3 | Asset-backed securities, backed by consumer loans | Measurement Input, Default Rate | Maximum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Securities, measurement input	0.412		0.412		0.352
Level 3 | Asset-backed securities, backed by consumer loans | Measurement Input, Default Rate | Weighted Average
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Securities, measurement input	0.204		0.204		0.213
Level 3 | Residential mortgage loans | Valuation, Income Approach | Performing Financial Instruments [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Total assets	$ 1,336,039		$ 1,336,039		$ 1,416,951
Level 3 | Residential mortgage loans | Measurement Input, Discount Rate | Performing Financial Instruments [Member] | Minimum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Loans, Measurement Input	0.007		0.007		0.005
Level 3 | Residential mortgage loans | Measurement Input, Discount Rate | Performing Financial Instruments [Member] | Maximum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Loans, Measurement Input	0.909		0.909		0.535
Level 3 | Residential mortgage loans | Measurement Input, Discount Rate | Performing Financial Instruments [Member] | Weighted Average
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Loans, Measurement Input	0.087		0.087		0.087
Level 3 | Commercial mortgage loans | Valuation, Income Approach | Performing Financial Instruments [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Total assets	$ 327,465		$ 327,465		$ 17,583
Level 3 | Commercial mortgage loans | Measurement Input, Discount Rate | Valuation, Income Approach | Performing Financial Instruments [Member] | Minimum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Loans, Measurement Input	0.062		0.062		0.230
Level 3 | Commercial mortgage loans | Measurement Input, Discount Rate | Valuation, Income Approach | Performing Financial Instruments [Member] | Maximum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Loans, Measurement Input	0.135		0.135		0.251
Level 3 | Commercial mortgage loans | Measurement Input, Discount Rate | Valuation, Income Approach | Performing Financial Instruments [Member] | Weighted Average
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Loans, Measurement Input	0.112		0.112		0.248
Level 3 | Consumer loans | Valuation, Income Approach
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Total assets	$ 3,059		$ 3,059		$ 4,843
Level 3 | Consumer loans | Measurement Input, Discount Rate | Valuation, Income Approach | Minimum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Loans, Measurement Input	0.104		0.104		0.106
Level 3 | Consumer loans | Measurement Input, Discount Rate | Valuation, Income Approach | Maximum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Loans, Measurement Input	0.279		0.279		0.282
Level 3 | Consumer loans | Measurement Input, Discount Rate | Valuation, Income Approach | Weighted Average
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Loans, Measurement Input	0.178		0.178		0.176
Level 3 | Consumer loans | Measurement Input, Prepayment Rate | Valuation, Income Approach | Minimum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Loans, Measurement Input	0.000		0.000		0.001
Level 3 | Consumer loans | Measurement Input, Prepayment Rate | Valuation, Income Approach | Maximum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Loans, Measurement Input	0.171		0.171		0.217
Level 3 | Consumer loans | Measurement Input, Prepayment Rate | Valuation, Income Approach | Weighted Average
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Loans, Measurement Input	0.075		0.075		0.122
Level 3 | Consumer loans | Measurement Input, Default Rate | Valuation, Income Approach | Minimum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Loans, Measurement Input	0.000		0.000		0.004
Level 3 | Consumer loans | Measurement Input, Default Rate | Valuation, Income Approach | Maximum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Loans, Measurement Input	0.447		0.447		0.612
Level 3 | Consumer loans | Measurement Input, Default Rate | Valuation, Income Approach | Weighted Average
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Loans, Measurement Input	0.145		0.145		0.132
Level 3 | Corporate loan [Member] | Valuation, Income Approach
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Total assets	$ 6,532		$ 6,532		$ 4,086
Level 3 | Corporate loan [Member] | Measurement Input, Discount Rate | Valuation, Income Approach | Minimum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Loans, Measurement Input	0.060		0.060		0.060
Level 3 | Corporate loan [Member] | Measurement Input, Discount Rate | Valuation, Income Approach | Maximum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Loans, Measurement Input	0.343		0.343		0.130
Level 3 | Corporate loan [Member] | Measurement Input, Discount Rate | Valuation, Income Approach | Weighted Average
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Loans, Measurement Input	0.137		0.137		0.071
Level 3 | Credit default swaps on asset-backed securities | Valuation, Income Approach
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Total assets	$ 76		$ 76		$ 76
Level 3 | Other secured borrowings, at fair value | Valuation, Market Approach
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value	$ (1,472,368)		$ (1,472,368)		$ (1,539,881)
Level 3 | Other secured borrowings, at fair value | Measurement Input, Quoted Price | Valuation, Market Approach | Minimum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Debt instrument, measurement input	49.09		49.09		54.94
Level 3 | Other secured borrowings, at fair value | Measurement Input, Quoted Price | Valuation, Market Approach | Maximum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Debt instrument, measurement input	98.10		98.10		98.22
Level 3 | Other secured borrowings, at fair value | Measurement Input, Quoted Price | Valuation, Market Approach | Weighted Average
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Debt instrument, measurement input	86.39		86.39		87.34
Level 3 | Other secured borrowings, at fair value | Measurement Input, Discount Rate | Valuation, Market Approach | Minimum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Debt instrument, measurement input	0.036		0.036		0.037
Level 3 | Other secured borrowings, at fair value | Measurement Input, Discount Rate | Valuation, Market Approach | Maximum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Debt instrument, measurement input	0.062		0.062		0.085
Level 3 | Other secured borrowings, at fair value | Measurement Input, Discount Rate | Valuation, Market Approach | Weighted Average
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Debt instrument, measurement input	0.054		0.054		0.069
Level 3 | Other secured borrowings, at fair value | Measurement Input, Prepayment Rate | Valuation, Market Approach | Minimum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Debt instrument, measurement input	0.931		0.931		0.933
Level 3 | Other secured borrowings, at fair value | Measurement Input, Prepayment Rate | Valuation, Market Approach | Maximum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Debt instrument, measurement input	0.953		0.953		0.963
Level 3 | Other secured borrowings, at fair value | Measurement Input, Prepayment Rate | Valuation, Market Approach | Weighted Average
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Debt instrument, measurement input	0.941		0.941		0.945
Level 3 | Investment in unconsolidated entities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Total assets	$ 118,420		$ 118,420		$ 127,046
Level 3 | Investment in unconsolidated entities | Measurement Input, Net Asset Value | Enterprise Value
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Total assets	85,360		85,360		88,905
Level 3 | Investment in unconsolidated entities | Measurement Input, Exercise Price | Valuation, Cost Approach
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Total assets	542		542		1,042
Level 3 | Senior Notes | Valuation, Market Approach
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value	$ (185,325)		$ (185,325)		$ (191,835)
Level 3 | Senior Notes | Measurement Input, Quoted Price | Valuation, Market Approach | Minimum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Debt instrument, measurement input	88.25		88.25		91.35
Level 3 | Senior Notes | Measurement Input, Quoted Price | Valuation, Market Approach | Maximum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Debt instrument, measurement input	88.25		88.25		91.35
Level 3 | Senior Notes | Measurement Input, Quoted Price | Valuation, Market Approach | Weighted Average
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Debt instrument, measurement input	88.25		88.25		91.35
Level 3 | HECM loans | Valuation, Cost Approach
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Total assets	$ 23,676		$ 23,676
Level 3 | HECM loans | Valuation, Income Approach
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Total assets	$ 8,262,333		$ 8,262,333		$ 7,993,635
Level 3 | HECM loans | Measurement Input, Discount Rate | Valuation, Income Approach | Minimum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Loans, Measurement Input	0.025		0.025		0.042
Level 3 | HECM loans | Measurement Input, Discount Rate | Valuation, Income Approach | Maximum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Loans, Measurement Input	0.071		0.071		0.063
Level 3 | HECM loans | Measurement Input, Discount Rate | Valuation, Income Approach | Weighted Average
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Loans, Measurement Input	0.048		0.048		0.052
Level 3 | HECM loans | Measurement Input, Prepayment Rate | Valuation, Income Approach | Minimum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Loans, Measurement Input	0.079		0.079		0.018
Level 3 | HECM loans | Measurement Input, Prepayment Rate | Valuation, Income Approach | Maximum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Loans, Measurement Input	0.453		0.453		0.446
Level 3 | HECM loans | Measurement Input, Prepayment Rate | Valuation, Income Approach | Weighted Average
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Loans, Measurement Input	0.093		0.093		0.098
Level 3 | Proprietary reverse mortgage loans | Valuation, Income Approach
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Total assets	$ 185,052		$ 185,052		$ 103,602
Level 3 | Proprietary reverse mortgage loans | Measurement Input, Discount Rate | Valuation, Income Approach | Minimum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Loans, Measurement Input	0.059		0.059		0.065
Level 3 | Proprietary reverse mortgage loans | Measurement Input, Discount Rate | Valuation, Income Approach | Maximum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Loans, Measurement Input	0.092		0.092		0.086
Level 3 | Proprietary reverse mortgage loans | Measurement Input, Discount Rate | Valuation, Income Approach | Weighted Average
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Loans, Measurement Input	0.075		0.075		0.081
Level 3 | Proprietary reverse mortgage loans | Measurement Input, Prepayment Rate | Valuation, Income Approach | Minimum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Loans, Measurement Input	0.110		0.110		0.110
Level 3 | Proprietary reverse mortgage loans | Measurement Input, Prepayment Rate | Valuation, Income Approach | Maximum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Loans, Measurement Input	0.371		0.371		0.371
Level 3 | Proprietary reverse mortgage loans | Measurement Input, Prepayment Rate | Valuation, Income Approach | Weighted Average
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Loans, Measurement Input	0.147		0.147		0.138
Level 3 | Mortgage servicing rights | Valuation, Income Approach
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Total assets	$ 7,473		$ 7,473		$ 8,108
Level 3 | Mortgage servicing rights | Measurement Input, Discount Rate | Valuation, Market Approach | Minimum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Servicing Asset, Measurement Input	0.120		0.120		0.120
Level 3 | Mortgage servicing rights | Measurement Input, Discount Rate | Valuation, Market Approach | Maximum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Servicing Asset, Measurement Input	0.120		0.120		0.120
Level 3 | Mortgage servicing rights | Measurement Input, Discount Rate | Valuation, Market Approach | Weighted Average
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Servicing Asset, Measurement Input	0.120		0.120		0.120
Level 3 | Mortgage servicing rights | Measurement Input, Prepayment Rate | Valuation, Market Approach | Minimum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Servicing Asset, Measurement Input	0.110		0.110		0.110
Level 3 | Mortgage servicing rights | Measurement Input, Prepayment Rate | Valuation, Market Approach | Maximum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Servicing Asset, Measurement Input	0.371		0.371		0.371
Level 3 | Mortgage servicing rights | Measurement Input, Prepayment Rate | Valuation, Market Approach | Weighted Average
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Servicing Asset, Measurement Input	0.140		0.140		0.147
Level 3 | Servicing-related asset | Valuation, Income Approach
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Total assets	$ 1,304		$ 1,304		$ 999
Level 3 | Servicing-related asset | Measurement Input, Discount Rate | Valuation, Market Approach | Minimum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Servicing Asset, Measurement Input	0.117		0.117		0.117
Level 3 | Servicing-related asset | Measurement Input, Discount Rate | Valuation, Market Approach | Maximum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Servicing Asset, Measurement Input	0.117		0.117		0.117
Level 3 | Servicing-related asset | Measurement Input, Discount Rate | Valuation, Market Approach | Weighted Average
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Servicing Asset, Measurement Input	0.117		0.117		0.117
Level 3 | Loan commitments | Valuation, Income Approach
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Total assets	$ 3,800		$ 3,800		$ 3,060
Level 3 | Loan commitments | Measurement Input pullthrough rate | Valuation, Market Approach | Minimum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Servicing Asset, Measurement Input	0.606		0.606		0.562
Level 3 | Loan commitments | Measurement Input pullthrough rate | Valuation, Market Approach | Maximum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Servicing Asset, Measurement Input	1.000		1.000		1.000
Level 3 | Loan commitments | Measurement Input pullthrough rate | Valuation, Market Approach | Weighted Average
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Servicing Asset, Measurement Input	0.750		0.750		0.737
Level 3 | Loan commitments | measurement input cost to originate loan | Valuation, Market Approach | Minimum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Servicing Asset, Measurement Input	0.030		0.030		0.024
Level 3 | Loan commitments | measurement input cost to originate loan | Valuation, Market Approach | Maximum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Servicing Asset, Measurement Input	0.078		0.078		0.071
Level 3 | Loan commitments | measurement input cost to originate loan | Valuation, Market Approach | Weighted Average
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Servicing Asset, Measurement Input	0.055		0.055		0.044
Level 3 | HMBS-related obligations | Valuation, Market Approach
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value	$ (8,055,288)		$ (8,055,288)		$ (7,787,155)
Level 3 | HMBS-related obligations | Measurement Input, Discount Rate | Valuation, Market Approach | Minimum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Debt instrument, measurement input	0.023		0.023		0.041
Level 3 | HMBS-related obligations | Measurement Input, Discount Rate | Valuation, Market Approach | Maximum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Debt instrument, measurement input	0.070		0.070		0.061
Level 3 | HMBS-related obligations | Measurement Input, Discount Rate | Valuation, Market Approach | Weighted Average
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Debt instrument, measurement input	0.047		0.047		0.051
Level 3 | HMBS-related obligations | Measurement Input, Prepayment Rate | Valuation, Market Approach | Minimum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Debt instrument, measurement input	0.080		0.080		0.073
Level 3 | HMBS-related obligations | Measurement Input, Prepayment Rate | Valuation, Market Approach | Maximum
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Debt instrument, measurement input	0.453		0.453		0.367
Level 3 | HMBS-related obligations | Measurement Input, Prepayment Rate | Valuation, Market Approach | Weighted Average
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Debt instrument, measurement input	0.092		0.092		0.098
Level 3 | Other secured borrowings, at fair value
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Liabilities, Payments				213,953
Liabilities, Issuances				(800,866)
Liabilities, Begining Balance	$ (1,534,592)	1,216,542	$ (1,539,881)	(984,168)
Liabilities, Accreted Discounts/Amortized Premiums	(261)	0	(664)	0
Liabilities, Realized Gain/(Loss)	0	0	0	0
Liabilities, Change In Net Unrealized Gain/(Loss)	12,152	67,258	(17,527)	122,899
Liabilities Purchases/Payments	50,333	99,198	85,704
Liabilities, Sales/Issuance	0	398,096	0
Liabilities, Transfers into Level 3	0	0	0	0
Liabilities, Transfers out of Level 3	0	0	0	0
Liabilities, Ending Balance	(1,472,368)	(1,448,182)	(1,472,368)	(1,448,182)
Change in unrealized gains (losses), liabilities	12,200		(17,500)	122,900
Fair Value, Asset (Liability), Recurring Basis, Still Held, Unrealized Gain (Loss)		67,300
Level 3 | Senior notes
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Liabilities, Begining Balance			(191,835)	0
Liabilities, Accreted Discounts/Amortized Premiums			0	0
Liabilities, Realized Gain/(Loss)			0	0
Liabilities, Change In Net Unrealized Gain/(Loss)			6,510	7,350
Liabilities Purchases/Payments			0	0
Liabilities, Sales/Issuance			0	(210,000)
Liabilities, Transfers into Level 3			0	0
Liabilities, Transfers out of Level 3			0	0
Liabilities, Ending Balance	(185,325)	(202,650)	(185,325)	(202,650)
Level 3 | Senior Notes
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Liabilities, Begining Balance	(185,325)	210,000
Liabilities, Accreted Discounts/Amortized Premiums	0	0
Liabilities, Realized Gain/(Loss)	0	0
Liabilities, Change In Net Unrealized Gain/(Loss)	0	7,350
Liabilities Purchases/Payments	0	0
Liabilities, Sales/Issuance	0	0
Liabilities, Transfers into Level 3	0	0
Liabilities, Transfers out of Level 3	0	0
Liabilities, Ending Balance	(185,325)	(202,650)	(185,325)	(202,650)
Change in unrealized gains (losses), liabilities		7,400	6,500	7,400
Level 3 | HMBS-related obligations
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Liabilities, Begining Balance	(7,975,916)		(7,787,155)
Liabilities, Accreted Discounts/Amortized Premiums	0		0
Liabilities, Realized Gain/(Loss)	0		0
Liabilities, Change In Net Unrealized Gain/(Loss)	(24,577)		(156,111)
Liabilities Purchases/Payments	340,499		616,117
Liabilities, Sales/Issuance	395,294		(728,139)
Liabilities, Transfers into Level 3	0		0
Liabilities, Transfers out of Level 3	0		0
Liabilities, Ending Balance	(8,055,288)		(8,055,288)
Change in unrealized gains (losses), liabilities	(24,600)		(156,100)
Level 3 | Securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Change in unrealized gain (loss), assets	(6,600)	(17,900)	(12,000)	(22,600)
Level 3 | Securities | Agency RMBS
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Assets, Beginning Balance	6,193	8,621	7,027	9,710
Assets, Accreted Discounts/Amortized Premiums	(322)	(672)	(641)	(1,088)
Assets, Realized Gain (Loss)	(176)	(250)	(464)	133
Assets, Change In Net Unrealized Gain/(Loss)	3	206	421	(1,182)
Assets, Purchases	195	441	336	840
Assets, Sales	0	0	(964)	(514)
Assets, Transfers into Level 3	959	4,043	1,136	4,805
Assets, Transfers out of Level 3	1,497	0	(1,496)	(315)
Assets, Ending Balance	5,355	12,389	5,355	12,389
Level 3 | Securities | Non-Agency RMBS
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Assets, Beginning Balance	156,277	116,776	132,502	134,888
Assets, Accreted Discounts/Amortized Premiums	(85)	208	101	783
Assets, Realized Gain (Loss)	1,035	2,076	1,926	1,951
Assets, Change In Net Unrealized Gain/(Loss)	(3,873)	(6,407)	(7,917)	(9,458)
Assets, Purchases	1,134	15,577	28,889	18,614
Assets, Sales	8,742	5,096	(31,391)	(12,160)
Assets, Transfers into Level 3	29,517	12,048	51,229	17,710
Assets, Transfers out of Level 3	6,654	3,733	(6,730)	(20,879)
Assets, Ending Balance	168,609	131,449	168,609	131,449
Level 3 | Securities | CMBS
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Assets, Beginning Balance	11,767	9,526	12,649	13,134
Assets, Accreted Discounts/Amortized Premiums	54	32	103	61
Assets, Realized Gain (Loss)	0	(24)	0	1,118
Assets, Change In Net Unrealized Gain/(Loss)	(1,083)	(533)	(2,488)	(1,281)
Assets, Purchases	2,126	0	2,127	620
Assets, Sales	0	0	0	(2,234)
Assets, Transfers into Level 3	2,016	379	2,742	5,119
Assets, Transfers out of Level 3	2,572	0	2,825	7,157
Assets, Ending Balance	12,308	9,380	12,308	9,380
Level 3 | Securities | CLOs
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Assets, Beginning Balance	28,674	22,824	24,598	26,678
Assets, Accreted Discounts/Amortized Premiums	(229)	(557)	(64)	(1,420)
Assets, Realized Gain (Loss)	354	2,067	239	3,020
Assets, Change In Net Unrealized Gain/(Loss)	(954)	(3,915)	(2,232)	(2,947)
Assets, Purchases	2,751	26	728	0
Assets, Sales	10,863	4,724	(6,874)	(10,480)
Assets, Transfers into Level 3	0	9,861	3,338	10,731
Assets, Transfers out of Level 3	0	2,204	0	(2,204)
Assets, Ending Balance	19,733	23,378	19,733	23,378
Level 3 | Securities | Asset-backed securities, backed by consumer loans
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Assets, Beginning Balance	72,200	76,504	73,644	73,108
Assets, Accreted Discounts/Amortized Premiums	(991)	(1,040)	(2,318)	(2,153)
Assets, Realized Gain (Loss)	(6,787)	(26)	(6,709)	(299)
Assets, Change In Net Unrealized Gain/(Loss)	4,209	(3,608)	2,137	(5,632)
Assets, Purchases	17,553	17,444	29,693	36,237
Assets, Sales	9,045	11,091	(19,308)	(23,078)
Assets, Transfers into Level 3	0	0	0	0
Assets, Transfers out of Level 3	0	0	0	0
Assets, Ending Balance	77,139	78,183	77,139	78,183
Level 3 | Securities | Corporate debt securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Assets, Beginning Balance	8,347	500	7,533	5,198
Assets, Accreted Discounts/Amortized Premiums	0	0	0	0
Assets, Realized Gain (Loss)	(832)	(1)	(1,089)	1,533
Assets, Change In Net Unrealized Gain/(Loss)	469	(172)	740	(1,680)
Assets, Purchases	8,359	3,584	11,253	5,312
Assets, Sales	6,710	2,144	(8,804)	(8,596)
Assets, Transfers into Level 3	0	0	0	0
Assets, Transfers out of Level 3	0	0	0	0
Assets, Ending Balance	9,633	1,767	9,633	1,767
Level 3 | Securities | Corporate equity securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Assets, Beginning Balance	11,102	9,841	11,111	7,556
Assets, Accreted Discounts/Amortized Premiums	0	0	0	0
Assets, Realized Gain (Loss)	(4)	114	(3)	1,739
Assets, Change In Net Unrealized Gain/(Loss)	422	(535)	381	(1,365)
Assets, Purchases	1,062	856	1,094	4,983
Assets, Sales	1,846	0	(1,847)	(2,637)
Assets, Transfers into Level 3	0	0	0	0
Assets, Transfers out of Level 3	0	0	0	0
Assets, Ending Balance	10,736	10,276	10,736	10,276
Level 3 | Loans
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Change in unrealized gain (loss), assets	(11,200)	(114,000)	42,700	(184,400)
Level 3 | Loans | Residential mortgage loans
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Assets, Beginning Balance	3,024,744	2,433,007	3,115,518	2,016,228
Assets, Accreted Discounts/Amortized Premiums	(2,571)	(4,544)	(4,232)	(9,011)
Assets, Realized Gain (Loss)	(2,938)	105	(8,526)	1,617
Assets, Change In Net Unrealized Gain/(Loss)	(15,200)	(112,735)	38,444	(183,248)
Assets, Purchases	359,090	896,384	679,302	1,619,479
Assets, Sales	369,442	216,633	(826,823)	(449,481)
Assets, Transfers into Level 3	0	0	0	0
Assets, Transfers out of Level 3	0	0	0	0
Assets, Ending Balance	2,993,683	2,995,584	2,993,683	2,995,584
Level 3 | Loans | Commercial mortgage loans
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Assets, Beginning Balance	374,233	429,954	404,324	326,197
Assets, Accreted Discounts/Amortized Premiums	0	0	0	0
Assets, Realized Gain (Loss)	0	0	(1)	10
Assets, Change In Net Unrealized Gain/(Loss)	4,254	(1,388)	4,594	(1,224)
Assets, Purchases	27,225	66,164	63,445	333,806
Assets, Sales	57,352	17,352	(124,002)	(181,411)
Assets, Transfers into Level 3	0	0	0	0
Assets, Transfers out of Level 3	0	0	0	0
Assets, Ending Balance	348,360	477,378	348,360	477,378
Level 3 | Loans | Consumer loans
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Assets, Beginning Balance	3,969	9,878	4,843	62,365
Assets, Accreted Discounts/Amortized Premiums	(230)	(384)	(476)	(2,523)
Assets, Realized Gain (Loss)	(292)	(518)	(196)	(698)
Assets, Change In Net Unrealized Gain/(Loss)	210	94	(44)	(371)
Assets, Purchases	151	37	451	10,982
Assets, Sales	749	1,697	(1,519)	(62,345)
Assets, Transfers into Level 3	0	0	0	0
Assets, Transfers out of Level 3	0	0	0	0
Assets, Ending Balance	3,059	7,410	3,059	7,410
Level 3 | Loans | Corporate loan [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Assets, Beginning Balance	4,920	11,788	4,086	10,531
Assets, Accreted Discounts/Amortized Premiums	0	0	0	0
Assets, Realized Gain (Loss)	454	(1,000)	354	(1,000)
Assets, Change In Net Unrealized Gain/(Loss)	9	0	10	0
Assets, Purchases	2,481	675	3,417	2,325
Assets, Sales	1,332	1,015	(1,335)	(1,408)
Assets, Transfers into Level 3	0	0	0	0
Assets, Transfers out of Level 3	0	0	0	0
Assets, Ending Balance	6,532	10,448	6,532	10,448
Level 3 | Loans | Reverse mortgage loans
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Assets, Beginning Balance	8,404,701		8,097,237
Assets, Accreted Discounts/Amortized Premiums	0		0
Assets, Realized Gain (Loss)	0		(4)
Assets, Change In Net Unrealized Gain/(Loss)	39,393		210,961
Assets, Purchases	424,893		845,371
Assets, Sales	397,926		(682,504)
Assets, Transfers into Level 3	0		0
Assets, Transfers out of Level 3	0		0
Assets, Ending Balance	8,471,061		8,471,061
Level 3 | Investment in unconsolidated entities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Assets, Beginning Balance	118,747	219,303	127,046	195,643
Assets, Accreted Discounts/Amortized Premiums	0	0	0	0
Assets, Realized Gain (Loss)	(1,245)	262	227	1,140
Assets, Change In Net Unrealized Gain/(Loss)	(4,623)	(23,527)	(2,651)	(29,911)
Assets, Purchases	50,816	56,701	81,602	195,909
Assets, Sales	45,275	60,470	(87,804)	(170,512)
Assets, Transfers into Level 3	0	0	0	0
Assets, Transfers out of Level 3	0	0	0	0
Assets, Ending Balance	118,420	192,269	118,420	192,269
Change in unrealized gain (loss), assets	(6,700)	(26,200)	(8,800)	(34,000)
Level 3 | Financial Derivatives - Assets
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Change in unrealized gain (loss), assets		(100)		(100)
Level 3 | Financial Derivatives - Assets | Credit default swaps on asset-backed securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Assets, Beginning Balance	76	304	76	303
Assets, Accreted Discounts/Amortized Premiums	0	0	0	0
Assets, Realized Gain (Loss)	0	(6)	1	(11)
Assets, Change In Net Unrealized Gain/(Loss)	0	(102)	0	(101)
Assets, Purchases	0	6	0	11
Assets, Sales	0	0	(1)	0
Assets, Transfers into Level 3	0	0	0	0
Assets, Transfers out of Level 3	0	0	0	0
Assets, Ending Balance	76	$ 202	76	$ 202
Level 3 | Mortgage servicing rights
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Assets, Beginning Balance	8,100		8,108
Assets, Accreted Discounts/Amortized Premiums	0		0
Assets, Realized Gain (Loss)	0		0
Assets, Change In Net Unrealized Gain/(Loss)	(627)		(635)
Assets, Purchases	0		0
Assets, Sales	0		0
Assets, Transfers into Level 3	0		0
Assets, Transfers out of Level 3	0		0
Assets, Ending Balance	7,473		7,473
Change in unrealized gain (loss), assets	(600)		(600)
Level 3 | Servicing-related asset
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Assets, Beginning Balance	299		999
Assets, Accreted Discounts/Amortized Premiums	0		0
Assets, Realized Gain (Loss)	0		0
Assets, Change In Net Unrealized Gain/(Loss)	1,005		305
Assets, Purchases	0		0
Assets, Sales	0		0
Assets, Transfers into Level 3	0		0
Assets, Transfers out of Level 3	0		0
Assets, Ending Balance	1,304		1,304
Change in unrealized gain (loss), assets			300
Level 3 | Loan commitments
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Assets, Beginning Balance	3,299		3,060
Assets, Accreted Discounts/Amortized Premiums	0		0
Assets, Realized Gain (Loss)	0		0
Assets, Change In Net Unrealized Gain/(Loss)	501		740
Assets, Purchases	0		0
Assets, Sales	0		0
Assets, Transfers into Level 3	0		0
Assets, Transfers out of Level 3	0		0
Assets, Ending Balance	3,800		3,800
Change in unrealized gain (loss), assets	$ 500		$ 700