
	Held-to-maturity								Available-for-sale
(Dollars in thousands)	Amortized cost		Unrecognized gain		Unrecognized loss		Fair value		Amortized cost		Unrealized gain		Unrealized loss		Fair value
U.S. Treasuries	$	0	$	0	$	0	$	0	$	10,257	$	3	$	0	$	10,260

Mortgage-backed securities - residential	0		0		0		0		784,407		12,488		(11,255)		785,640
Mortgage-backed securities - commercial	63,481		2,034		0		65,515		591,629		7,096		(3,680)		595,045
Collateralized mortgage obligations	17,580		109		(411)		17,278		661,322		17,796		(2,404)		676,714
Obligations of state and other political subdivisions	9,634		1,001		0		10,635		971,325		38,835		(8,541)		1,001,619
Asset-backed securities	0		0		0		0		601,836		4,075		(1,190)		604,721
Other securities	31,250		82		(466)		30,866		78,003		1,949		(188)		79,764
Total	$	121,945	$	3,226	$	(877)	$	124,294	$	3,698,779	$	82,242	$	(27,258)	$	3,753,763


	Held-to-maturity								Available-for-sale
(Dollars in thousands)	Amortized cost		Unrecognized gain		Unrecognized loss		Fair value		Amortized cost		Unrealized gain		Unrealized loss		Fair value
U.S. Treasuries	$	0	$	0	$	0	$	0	$	99	$	4	$	0	$	103
Securities of U.S. government agencies and corporations	0		0		0		0		60		0		0		60
Mortgage-backed securities - residential	13,990		197		0		14,187		704,482		15,938		(237)		720,183
Mortgage-backed securities - commercial	71,737		3,485		0		75,222		584,125		10,395		(3,584)		590,936
Collateralized mortgage obligations	5,799		79		0		5,878		634,418		21,148		(445)		655,121
Obligations of state and other political subdivisions	9,911		1,239		0		11,150		856,054		46,755		(291)		902,518
Asset-backed securities	0		0		0		0		478,539		4,158		(826)		481,871
Other securities	30,250		11		0		30,261		72,252		1,544		(8)		73,788
Total	$	131,687	$	5,011	$	0	$	136,698	$	3,330,029	$	99,942	$	(5,391)	$	3,424,580

The following table provides a summary of investment securities by contractual maturity as of March 31, 2021, except for residential and commercial mortgage-backed securities, collateralized mortgage obligations and asset-backed securities, which are shown as single totals due to the unpredictability of the timing in principal repayments.


	Held-to-maturity				Available-for-sale
(Dollars in thousands)	Amortized cost		Fair value		Amortized cost		Fair value
By Contractual Maturity:
Due in one year or less	$	0	$	0	$	14,781	$	14,963
Due after one year through five years	0		0		56,598		58,309
Due after five years through ten years	37,135		37,662		184,348		192,197
Due after ten years	3,749		3,839		803,858		826,174
Mortgage-backed securities - residential	0		0		784,407		785,640
Mortgage-backed securities - commercial	63,481		65,515		591,629		595,045
Collateralized mortgage obligations	17,580		17,278		661,322		676,714
Asset-backed securities	0		0		601,836		604,721
Total	$	121,945	$	124,294	$	3,698,779	$	3,753,763

Unrealized gains and losses on debt securities are generally due to fluctuations in current market yields relative to the yields of the debt securities at their amortized cost. All securities with unrealized losses are reviewed quarterly to determine if any impairment exists, requiring a write-down to fair value. For securities in an unrealized loss position, the Company first assesses

whether it intends to sell or it is more likely than not that it will be required to sell the security before recovery of its amortized cost basis. If either of the criteria regarding intent or requirement to sell is met, the security’s amortized cost basis is written down to fair value through income. For debt securities available-for-sale that do not meet the aforementioned criteria, the Company evaluates whether the decline in fair value has resulted from credit losses or other factors. In making this assessment, management considers the extent to which fair value is less than amortized cost, any changes to the rating of the security by a rating agency and adverse conditions specifically related to the security, among other factors. If this assessment indicates that a credit loss exists, the present value of cash flows expected to be collected from the security are compared to the amortized cost basis of the security.

At this time, First Financial does not intend to sell, and it is not more likely than not that the Company will be required to sell, debt securities temporarily impaired prior to maturity or recovery of the recorded value. The Company recorded no reserves on investment securities for the three months ended March 31, 2021 or the twelve months ended December 31, 2020.

As of March 31, 2021, the Company's investment securities portfolio consisted of 1,402 securities, of which 223 were in an unrealized loss position. As of December 31, 2020, the Company's investment securities portfolio consisted of 1,351 securities, of which 94 were in an unrealized loss position.

Primarily all of First Financial’s HTM debt securities are issued by U.S. government-sponsored enterprises. These securities carry the explicit and/or implicit guarantee of the U.S. government, are widely recognized as “risk free,” and have a long history of zero credit loss. The remainder of the Company's HTM securities are non-agency collateralized mortgage obligations and obligations of state and other political subdivisions which currently carry ratings no lower than A+. There were no HTM securities on nonaccrual status or past due as of March 31, 2021 or December 31, 2020. Therefore, the Company did not record an allowance for credit losses for these securities as of March 31, 2021 or December 31, 2020.

The following tables provide the fair value and gross unrealized losses on investment securities in an unrealized loss position for which an allowance for credit losses has not been recorded, aggregated by investment category and the length of time the individual securities have been in a continuous loss position:


	March 31, 2021
	Less than 12 months				12 months or more				Total
(Dollars in thousands)	Fair value		Unrealized loss		Fair value		Unrealized loss		Fair value		Unrealized loss
U.S. Treasuries	$	0	$	0	$	0	$	0	$	0	$	0
Securities of U.S. Government agencies and corporations	0		0		0		0		0		0
Mortgage-backed securities - residential	482,754		(11,255)		0		0		482,754		(11,255)
Mortgage-backed securities - commercial	60,681		(1,665)		57,196		(2,015)		117,877		(3,680)
Collateralized mortgage obligations	142,823		(2,815)		1		0		142,824		(2,815)
Obligations of state and other political subdivisions	318,750		(8,527)		22,104		(14)		340,854		(8,541)
Asset-backed securities	160,329		(970)		36,344		(220)		196,673		(1,190)
Other securities	34,096		(654)		0		0		34,096		(654)
Total	$	1,199,433	$	(25,886)	$	115,645	$	(2,249)	$	1,315,078	$	(28,135)


	December 31, 2020
	Less than 12 months				12 months or more				Total
(Dollars in thousands)	Fair value		Unrealized loss		Fair value		Unrealized loss		Fair value		Unrealized loss
U.S. Treasuries	$	0	$	0	$	0	$	0	$	0	$	0
Securities of U.S. Government agencies and corporations	0		0		0		0		0		0
Mortgage-backed securities - residential	57,872		(237)		0		0		57,872		(237)
Mortgage-backed securities - commercial	169,825		(986)		48,158		(2,598)		217,983		(3,584)
Collateralized mortgage obligations	49,161		(445)		1		0		49,162		(445)
Obligations of state and other political subdivisions	60,008		(291)		0		0		60,008		(291)
Asset-backed securities	84,749		(435)		68,967		(391)		153,716		(826)
Other securities	4,992		(8)		0		0		4,992		(8)
Total	$	426,607	$	(2,402)	$	117,126	$	(2,989)	$	543,733	$	(5,391)