Investment in Securities (Summary of Investment Income) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Securities, Available-for-sale [Line Items]
Interest Income	$ 51,074	$ 40,079
Level 3
Securities, Available-for-sale [Line Items]
Assets, Transfers into Level 3	13,300	9,366
Agency RMBS
Securities, Available-for-sale [Line Items]
Coupon Interest	14,335	14,352
Net Amortization	(6,137)	(7,600)
Interest Income	8,198	6,752
Non-Agency RMBS and CMBS
Securities, Available-for-sale [Line Items]
Coupon Interest	4,086	3,756
Net Amortization	28	1,467
Interest Income	4,114	5,223
CLOs
Securities, Available-for-sale [Line Items]
Coupon Interest	1,729	2,536
Net Amortization	(585)	944
Interest Income	1,144	3,480
Other Securities
Securities, Available-for-sale [Line Items]
Coupon Interest	5,557	3,533
Net Amortization	(1,113)	(657)
Interest Income	4,444	2,876
Securities Investment [Member]
Securities, Available-for-sale [Line Items]
Coupon Interest	25,707	24,177
Net Amortization	(7,807)	(5,846)
Interest Income	$ 17,900	$ 18,331

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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-Section 45
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- Definition

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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- Definition

Amount of operating interest income, including, but not limited to, amortization and accretion of premiums and discounts on securities.

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Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities.

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-Publisher FASB
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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