(4) Commercial Mortgage-Backed Securities

During the nine months ended September 30, 2018, the Company purchased for short-term cash management and investment purposes 17 CMBS investments for $138.0 million. The purchased CMBS investments consist of floating rate instruments which, in the aggregate, had a weighted average coupon of 2.9%. No CMBS investments were purchased during the three months ended September 30, 2018. In July 2018, the Company sold 17 CMBS investments for total cash consideration of $133.3 million, including selling costs and fees, recognizing a loss on the sale of $0.1 million, which is recorded in Other (Loss) Income, net.

As of September 30, 2018 and December 31, 2017, the Company had four and five CMBS, respectively, designated as available-for-sale securities. Details of the carrying and fair values of the Company’s CMBS portfolio are as follows (dollars in thousands):

	September 30, 2018
	Face Amount		Unamortized Premium (Discount), net			Gross Unrealized Loss			Estimated Fair Value
Investments, at Fair Value
Commercial mortgage-backed securities	$	76,603	$	(40	)	$	(1,149	)	$	75,414

	December 31, 2017
	Face Amount		Unamortized Premium (Discount), net		Gross Unrealized Loss			Estimated Fair Value
Investments, at Fair Value
Commercial mortgage-backed securities	$	85,661	$	268	$	(34	)	$	85,895

CMBS fair values are considered Level II fair value measurements within the fair value hierarchy of ASC 820-10. The CMBS fair values are based upon market, broker, and counterparty or pricing services quotations, which provide valuation estimates, based upon reasonable market order indications. The Company reviews the fair value quotations, which are subject to significant variability based on market conditions, such as interest rates, credit spreads and market liquidity, for reasonableness and consistency.

The Company’s CMBS have a weighted average contractual maturity, based on estimated fair value, of 15.0 years. The amortized cost and estimated fair value of the Company’s available-for-sale CMBS by contractual maturity are shown in the following table (dollars in thousands):

	September 30, 2018
	Amortized Cost		Estimated Fair Value
Maturity Date
After one, within five years	$	37,937	$	38,072
After five years		38,627		37,342
Total investment in commercial mortgage-backed securities, at amortized cost and estimated fair value	$	76,564	$	75,414

	December 31, 2017
	Amortized Cost		Estimated Fair Value
Maturity Date
After one, within five years	$	36,700	$	36,872
After five years		49,229		49,023
Total investment in commercial mortgage-backed securities, at amortized cost and estimated fair value	$	85,929	$	85,895

Certain of the Company’s CMBS investments were in an unrealized loss position as of September 30, 2018. During the preceding 12 months these CMBS investments traded at, or near, their respective carrying values, and interest and principal payments are current. Additionally, as of September 30, 2018, substantially all of the unrealized loss position relates to CMBS investments issued by a government sponsored enterprise. Currently, all of the underlying mortgage loans are performing. No other-than-temporary impairments were recognized through income during the three or nine months ended September 30, 2018 or the year ended December 31, 2017.