Borrowings (Schedule of Debt Repayments) (Details) $ in Thousands	Sep. 30, 2020 USD ($)
Debt Instrument [Line Items]
Expected principal repayments related to consolidated residential mortgage loan securitizations	$ 734,300
Repurchase Agreements
Debt Instrument [Line Items]
Long-term Debt, Maturities, Repayments of Principal in Next Rolling Twelve Months	1,391,743
Long-term Debt, Maturities, Repayments of Principal in Rolling Year Two	48,241
2020 Scheduled Repayment of Principal	0
2021 Scheduled Repayment of Principal	0
Long-term Debt, Maturities, Repayments of Principal in Rolling after Year Five	0
Total Scheduled Repayment of Principal	1,439,984
Other Secured Borrowings
Debt Instrument [Line Items]
Long-term Debt, Maturities, Repayments of Principal in Next Rolling Twelve Months	523,802
Long-term Debt, Maturities, Repayments of Principal in Rolling Year Two	91,199
2020 Scheduled Repayment of Principal	261,991
2021 Scheduled Repayment of Principal	0
Long-term Debt, Maturities, Repayments of Principal in Rolling after Year Five	0
Total Scheduled Repayment of Principal	876,992
Senior Notes
Debt Instrument [Line Items]
Long-term Debt, Maturities, Repayments of Principal in Next Rolling Twelve Months	0
Long-term Debt, Maturities, Repayments of Principal in Rolling Year Two	86,000
2020 Scheduled Repayment of Principal	0
2021 Scheduled Repayment of Principal	0
Long-term Debt, Maturities, Repayments of Principal in Rolling after Year Five	0
Total Scheduled Repayment of Principal	86,000
Total
Debt Instrument [Line Items]
Long-term Debt, Maturities, Repayments of Principal in Next Rolling Twelve Months	1,915,545
Long-term Debt, Maturities, Repayments of Principal in Rolling Year Two	225,440
2020 Scheduled Repayment of Principal	261,991
2021 Scheduled Repayment of Principal	0
Long-term Debt, Maturities, Repayments of Principal in Rolling after Year Five	0
Total Scheduled Repayment of Principal	$ 2,402,976

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+ References

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+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
-Paragraph 3
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