Fair Value of Financial Instruments

A three-level valuation hierarchy exists for disclosure of fair value measurements based upon the transparency of inputs to the valuation of an asset or liability as of the measurement date. Observable inputs reflect readily obtainable data from independent sources, while unobservable inputs reflect our market assumptions. The three levels are defined as follows:


•	Level 1 Inputs – Quoted prices for identical instruments in active markets.


•	Level 2 Inputs – Quoted prices for similar instruments in active markets; quoted prices for identical or similar instruments in markets that are not active; and model-derived valuations whose inputs are observable or whose significant value drivers are observable.


•	Level 3 Inputs – Instruments with primarily unobservable value drivers.

The following tables present our assets and liabilities measured at fair value on a recurring basis.



	March 31, 2018
	Fair Value Measurements Using:
$ in thousands	Level 1	Level 2	Level 3	NAV as a practical expedient ⁽³⁾	Total at Fair Value
Assets:
Mortgage-backed and credit risk transfer securities ⁽¹⁾⁽²⁾	—	17,579,302	42,932	—	17,622,234
Derivative assets	—	26,385	—	—	26,385
Other assets ⁽⁴⁾	3,966	—	—	28,168	32,134
Total assets	3,966	17,605,687	42,932	28,168	17,680,753
Liabilities:
Derivative liabilities	1,612	18,742	—	—	20,354
Total liabilities	1,612	18,742	—	—	20,354



	December 31, 2017
	Fair Value Measurements Using:
$ in thousands	Level 1	Level 2	Level 3	NAV as a practical expedient ⁽³⁾	Total at Fair Value
Assets:
Mortgage-backed and credit risk transfer securities ⁽¹⁾⁽²⁾	—	18,145,354	45,400	—	18,190,754
Derivative assets	—	6,896	—	—	6,896
Other assets ⁽⁴⁾	3,979	—	—	25,972	29,951
Total assets	3,979	18,152,250	45,400	25,972	18,227,601
Liabilities:
Derivative liabilities	—	32,765	—	—	32,765
Total liabilities	—	32,765	—	—	32,765


(1)	For more detail about the fair value of our MBS and GSE CRTs, refer to Note 4 - "Mortgage-Backed and Credit Risk Transfer Securities."

(2)

Our GSE CRTs purchased prior to August 24, 2015 are accounted for as hybrid financial instruments with an embedded derivative. The hybrid financial instruments consist of debt host contracts classified as Level 2 and embedded derivatives classified as Level 3. As of March 31, 2018, the net embedded derivative asset position of $42.9 million includes $44.1 million of embedded derivatives in an asset position and $1.2 million of embedded derivatives in a liability position. As of December 31, 2017, the net embedded derivative asset position of $45.4 million includes $46.5 million of embedded derivatives in an asset position and $1.1 million of embedded derivatives in a liability position.

(3)

Investments in unconsolidated ventures are valued using the net asset value ("NAV") as a practical expedient and are not subject to redemption, although investors may sell or transfer their interest at the approval of the general partner of the underlying funds. As of March 31, 2018 and December 31, 2017, the weighted average remaining term of investments in unconsolidated ventures is 2.3 and 1.9 years, respectively.


(4)	Includes $4.0 million and $4.0 million of investment in an exchange-traded fund as of March 31, 2018 and December 31, 2017, respectively.

The following table shows a reconciliation of the beginning and ending fair value measurements of our GSE CRT embedded derivatives, which we have valued utilizing Level 3 inputs:



	Three Months Ended March 31,
$ in thousands	2018		2017
Beginning balance	45,400		17,095
Unrealized credit derivative gains (losses), net	(2,468	)	14,148
Ending balance	42,932		31,243

The following tables summarize significant unobservable inputs used in the fair value measurement of our GSE CRT embedded derivatives:



	Fair Value at	Valuation	Unobservable		Weighted
$ in thousands	March 31, 2018	Technique	Input	Range	Average
GSE CRT Embedded Derivatives	42,932	Market Comparables, Vendor Pricing	Weighted average life	2.5 - 6.6 years	4.6 years



	Fair Value at	Valuation	Unobservable		Weighted
$ in thousands	December 31, 2017	Technique	Input	Range	Average
GSE CRT Embedded Derivatives	45,400	Market Comparables, Vendor Pricing	Weighted average life	2.6 - 6.8 years	4.8 years

These significant unobservable inputs change according to market conditions and security performance. We estimate the weighted average life of GSE CRTs in order to identify GSE corporate debt with a similar maturity. We obtain our weighted average life estimates from a third party provider. Although weighted average life is a significant input, changes in weighted average life may not have an explicit directional impact on the fair value measurement.

The following table presents the carrying value and estimated fair value of our financial instruments that are not carried at fair value on the condensed consolidated balance sheets at March 31, 2018 and December 31, 2017:



	March 31, 2018		December 31, 2017
$ in thousands	Carrying Value	Estimated Fair Value	Carrying Value	Estimated Fair Value
Financial Assets
Commercial loans, held-for-investment	184,255	184,510	191,808	191,930
Other assets	74,250	74,250	74,250	74,250
Total	258,505	258,760	266,058	266,180
Financial Liabilities
Repurchase agreements	13,911,137	13,910,631	14,080,801	14,080,460
Secured loans	1,650,000	1,650,000	1,650,000	1,650,000
Exchangeable senior notes	—	—	143,231	143,948
Total	15,561,137	15,560,631	15,874,032	15,874,408

The following describes our methods for estimating the fair value for financial instruments.


•	The estimated fair value of commercial loans held-for-investment is a Level 3 fair value measurement. Subsequent to the origination or purchase, commercial loan investments are valued on a monthly basis by an independent third party valuation agent using a discounted cash flow technique.


•	The estimated fair value of FHLBI stock, included in "Other assets," is a Level 3 fair value measurement. FHLBI stock may only be sold back to the FHLBI at its discretion at cost. As a result, the cost of the FHLBI stock approximates its fair value.


•	The estimated fair value of repurchase agreements is a Level 3 fair value measurement based on an expected present value technique. This method discounts future estimated cash flows using rates we determined best reflect current market interest rates that would be offered for repurchase agreements with similar characteristics and credit quality.


•	The estimated fair value of secured loans is a Level 3 fair value measurement. The secured loans have floating rates based on an index plus a spread and the spread is typically consistent with those demanded in the market. Accordingly, the interest rates on these secured loans are at market, and thus the carrying amount approximates fair value.


•	The estimated fair value of exchangeable senior notes is a Level 2 fair value measurement based on a valuation obtained from a third-party pricing service.