Investment in Securities (Summary of Investment Income) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Securities, Available-for-sale [Line Items]
Interest Income	$ 62,722	$ 45,890	$ 113,796	$ 85,970
Level 3
Securities, Available-for-sale [Line Items]
Assets, Transfers into Level 3	26,331	13,806	38,365	12,005
Agency RMBS
Securities, Available-for-sale [Line Items]
Coupon Interest	12,941	14,300	27,276	28,652
Net Amortization	(1,892)	(2,972)	(8,029)	(10,572)
Interest Income	11,049	11,328	19,247	18,080
Non-Agency RMBS and CMBS
Securities, Available-for-sale [Line Items]
Coupon Interest	4,772	3,259	8,858	7,015
Net Amortization	103	964	131	2,431
Interest Income	4,875	4,223	8,989	9,446
CLOs
Securities, Available-for-sale [Line Items]
Coupon Interest	1,887	1,909	3,616	4,445
Net Amortization	(620)	571	(1,205)	1,515
Interest Income	1,267	2,480	2,411	5,960
Other Securities
Securities, Available-for-sale [Line Items]
Coupon Interest	4,587	4,173	10,144	7,706
Net Amortization	(1,036)	(1,326)	(2,149)	(1,983)
Interest Income	3,551	2,847	7,995	5,723
Securities Investment [Member]
Securities, Available-for-sale [Line Items]
Coupon Interest	24,187	23,641	49,894	47,818
Net Amortization	(3,445)	(2,763)	(11,252)	(8,609)
Interest Income	$ 20,742	$ 20,878	$ 38,642	$ 39,209

The sum of the periodic adjustments of the differences between securities' face values and purchase prices that are charged against earnings. This is called accretion if the security was purchased at a discount and amortization if it was purchased at premium. As a noncash item, this element is an adjustment to net income when calculating cash provided by or used in operations using the indirect method.

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Amount of transfer of financial instrument classified as an asset into level 3 of the fair value hierarchy.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
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Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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