Investment Securities (Tables)

6 Months Ended

Jun. 30, 2024

Investment Securities

Schedule of amortized cost and fair values of investment securities

	Amortized		Gross Unrealized				Estimated
(Dollars in thousands)	Cost		Gains		Losses		Fair Value			ACL
June 30, 2024:
Available-for-sale:
Mortgage-backed securities issued by U.S. government-sponsored enterprises	$	22,184	$	—	$	(3,089)	$	19,095	$	—
Held-to-maturity:
Mortgage-backed securities issued by U.S. government agencies or U.S. government-sponsored enterprises		666,103		7		(130,311)		535,799		—
Total	$	688,287	$	7	$	(133,400)	$	554,894	$	—
December 31, 2023:
Available-for-sale:
Mortgage-backed securities issued by U.S. government-sponsored enterprises	$	22,563	$	—	$	(2,392)	$	20,171	$	—
Held-to-maturity:
Mortgage-backed securities issued by U.S. government agencies or U.S. government-sponsored enterprises		685,728		68		(117,668)		568,128		—
Total	$	708,291	$	68	$	(120,060)	$	588,299	$	—

Schedule of amortized cost and estimated fair value of investment securities by maturity

	Amortized		Estimated
(Dollars in thousands)	Cost		Fair Value
Available-for-sale:
Due after 10 years	$	22,184	$	19,095
Total	$	22,184	$	19,095
Held-to-maturity:
Due within 5 years	$	12	$	12
Due after 5 years through 10 years		4		4
Due after 10 years		666,087		535,783
Total	$	666,103	$	535,799

Summary of investment securities in an unrealized loss position

	Less Than 12 Months				12 Months or Longer				Total
			Unrealized				Unrealized		Number of			Unrealized
Description of securities	Fair Value		Losses		Fair Value		Losses		Securities	Fair Value		Losses
(Dollars in thousands)
June 30, 2024:
Available-for-sale:
Mortgage-backed securities issued by U.S. government-sponsored enterprises	$	—	$	—	$	19,095	$	(3,089)	4	$	19,095	$	(3,089)
Held-to-maturity:
Mortgage-backed securities issued by U.S. government agencies or U.S. government-sponsored enterprises		476		(6)		532,700		(130,305)	154		533,176		(130,311)
Total	$	476	$	(6)	$	551,795	$	(133,394)	158	$	552,271	$	(133,400)
December 31, 2023:
Available-for-sale:
Mortgage-backed securities issued by U.S. government sponsored enterprises	$	—	$	—	$	20,171	$	(2,392)	4	$	20,171	$	(2,392)
Held-to-maturity:
Mortgage-backed securities issued by U.S. government agencies or U.S. government-sponsored enterprises		10,326		(107)		554,514		(117,561)	152		564,840		(117,668)
Total	$	10,326	$	(107)	$	574,685	$	(119,953)	156	$	585,011	$	(120,060)