Investment in Securities (Proceeds, Realized Gains (Losses) on Sales) (Details) $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($)
Debt Securities, Available-for-sale [Line Items]
Proceeds	$ 682,337
Agency RMBS
Debt Securities, Available-for-sale [Line Items]
Proceeds	128,304
Gross Realized Gains	712
Gross Realized Losses	(1,679)
Net Realized Gain (Loss)	(967)
Non-Agency RMBS and CMBS
Debt Securities, Available-for-sale [Line Items]
Proceeds	129,545
Gross Realized Gains	1,272
Gross Realized Losses	(3,443)
Net Realized Gain (Loss)	(2,171)
CLOs
Debt Securities, Available-for-sale [Line Items]
Proceeds	44,822
Gross Realized Gains	140
Gross Realized Losses	(935)
Net Realized Gain (Loss)	(795)
Other Securities
Debt Securities, Available-for-sale [Line Items]
Proceeds	405,903
Gross Realized Gains	758
Gross Realized Losses	(1,259)
Net Realized Gain (Loss)	(501)
Securities Total
Debt Securities, Available-for-sale [Line Items]
Proceeds	708,574
Gross Realized Gains	2,882
Gross Realized Losses	(7,316)
Net Realized Gain (Loss)	$ (4,434)

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Debt Securities, Available-for-sale Securities, Gross Realized Losses

+ References

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Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), investment in debt security measured at amortized cost (held-to-maturity) and investment in debt security measured at fair value with change in fair value recognized in net income (trading).

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Amount of cash inflow from sale of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 11
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Section 45
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