Securities

3 Months Ended

Mar. 31, 2022

Investments, Debt and Equity Securities [Abstract]

Investments in Debt and Marketable Equity Securities (and Certain Trading Assets) Disclosure [Text Block]

Securities

The following table summarizes the amortized cost, gross unrealized gains and losses and the resulting fair value of debt securities:

	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
March 31, 2022	(in thousands)
Available for sale
U.S. government agency and government-sponsored enterprise mortgage-backed securities and collateralized mortgage obligations	$	3,604,576	$	8,315	$	(205,237)	$	3,407,654
Other asset-backed securities	433,879		377		(26,209)		408,047
State and municipal securities	1,002,490		2,275		(65,800)		938,965
U.S. government agency and government-sponsored enterprise securities	247,727		711		(9,164)		239,274
U.S. government securities	182,500		—		(9,158)		173,342
Non-agency collateralized mortgage obligations	381,988		—		(21,899)		360,089
Total available for sale	$	5,853,160	$	11,678	$	(337,467)	$	5,527,371
Held to maturity
U.S. government agency and government-sponsored enterprise mortgage-backed securities and collateralized mortgage obligations	$	2,202,437	$	—	$	(164,400)	$	2,038,037
Total held to maturity	$	2,202,437	$	—	$	(164,400)	$	2,038,037
December 31, 2021
Available for sale
U.S. government agency and government-sponsored enterprise mortgage-backed securities and collateralized mortgage obligations	$	3,738,616	$	45,077	$	(38,092)	$	3,745,601
Other asset-backed securities	469,052		3,802		(9,791)		463,063
State and municipal securities	983,704		18,525		(4,938)		997,291
U.S. government agency and government-sponsored enterprise securities	252,755		3,095		(3,274)		252,576
U.S. government securities	158,367		—		(831)		157,536
Non-agency collateralized mortgage obligations	295,547		340		(955)		294,932
Total available for sale	$	5,898,041	$	70,839	$	(57,881)	$	5,910,999
Held to maturity
U.S. government agency and government-sponsored enterprise mortgage-backed securities and collateralized mortgage obligations	$	2,148,327	$	50	$	(25,771)	$	2,122,606
Total held to maturity	$	2,148,327	$	50	$	(25,771)	$	2,122,606

There was no allowance for credit losses on both available for sale securities and held to maturity securities as of March 31, 2022 and December 31, 2021. All of the Company’s debt securities held to maturity were issued by U.S. government agencies or 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.

A debt security is placed on nonaccrual status at the time any principal or interest payments become 90 days delinquent. Interest accrued but not received for a security placed on nonaccrual is reversed against interest income. There were no amounts of accrued interest reversed against interest income for the three months ended March 31, 2022 and 2021.

Accrued interest receivable for debt securities is included in “Interest receivable” on the Company’s Consolidated Balance Sheet and is not reflected in the balances in the table above. At March 31, 2022 and December 31, 2021, accrued interest receivable for securities available for sale was $18.4 million and $19.2 million, respectively. At March 31, 2022 and December 31, 2021, accrued interest receivable for securities held to maturity was $4.5 million and $4.4 million, respectively. The Company does not measure an allowance for credit losses for accrued interest receivable.

There were no proceeds or gross realized gains and losses on sales and calls of debt securities available for sale, nor were there other securities gains and losses for the three month periods ended March 31, 2022 and 2021. Additionally, there were no gains or losses recognized on equity securities during the three month periods ended March 31, 2022 and 2021.

The scheduled contractual maturities of debt securities at the period presented below are as follows:

	March 31, 2022
	Available for sale				Held to maturity
	Amortized Cost		Fair Value		Amortized Cost		Fair Value
	(in thousands)
Due within one year	$	92,542	$	92,902	$	—	$	—
Due after one year through five years	1,026,274		1,002,760		174,734		162,632
Due after five years through ten years	1,432,895		1,363,245		1,152,092		1,063,768
Due after ten years	3,301,449		3,068,464		875,611		811,637
Total debt securities	$	5,853,160	$	5,527,371	$	2,202,437	$	2,038,037

The following table summarizes the carrying value of securities pledged as collateral to secure public funds, borrowings and other purposes as permitted or required by law:

	March 31, 2022
	(in thousands)
To secure public funds	$	590,026
To secure borrowings	93,557
Other securities pledged	244,917
Total securities pledged as collateral	$	928,500

The following table shows the gross unrealized losses and fair value of the Company’s debt securities available for sale for which an allowance for credit losses has not been recorded, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position as of the dates presented:

	Less than 12 Months				12 Months or More				Total
	Fair Value		Unrealized Losses		Fair Value		Unrealized Losses		Fair Value		Unrealized Losses
March 31, 2022	(in thousands)
U.S. government agency and government-sponsored enterprise mortgage-backed securities and collateralized mortgage obligations	$	2,667,464	$	(181,337)	$	214,390	$	(23,900)	$	2,881,854	$	(205,237)
Other asset-backed securities	277,210		(16,208)		106,449		(10,001)		383,659		(26,209)
State and municipal securities	657,101		(57,012)		77,447		(8,788)		734,548		(65,800)
U.S. government agency and government-sponsored enterprise securities	25,502		(1,249)		118,135		(7,915)		143,637		(9,164)
U.S. government securities	173,342		(9,158)		—		—		173,342		(9,158)
Non-agency collateralized mortgage obligations	359,060		(21,899)		—		—		359,060		(21,899)
Total	$	4,159,679	$	(286,863)	$	516,421	$	(50,604)	$	4,676,100	$	(337,467)
December 31, 2021
U.S. government agency and government-sponsored enterprise mortgage-backed securities and collateralized mortgage obligations	$	2,292,062	$	(30,777)	$	176,946	$	(7,315)	$	2,469,008	$	(38,092)
Other asset-backed securities	195,708		(4,823)		117,751		(4,968)		313,459		(9,791)
State and municipal securities	237,354		(3,862)		40,343		(1,076)		277,697		(4,938)
U.S. government agency and government-sponsored enterprise securities	100,813		(1,988)		48,714		(1,286)		149,527		(3,274)
U.S. government securities	157,536		(831)		—		—		157,536		(831)
Non-agency collateralized mortgage obligations	212,259		(955)		—		—		212,259		(955)
Total	$	3,195,732	$	(43,236)	$	383,754	$	(14,645)	$	3,579,486	$	(57,881)

Debt securities available for sale

At March 31, 2022, there were 584 U.S. government agency and government-sponsored enterprise mortgage-backed securities and collateralized mortgage obligation securities in an unrealized loss position. The decline in fair value is attributable to changes in interest rates relative to where these investments fall within the yield curve and their individual characteristics. Because the Company does not intend to sell these securities nor does the Company consider it more likely than not that it will be required to sell these securities before the recovery of amortized cost basis, which may be upon maturity, the Company concluded an allowance for credit losses is unnecessary at March 31, 2022.

At March 31, 2022, there were 81 other asset-backed securities in an unrealized loss position. The decline in fair value is attributable to changes in interest rates relative to where these investments fall within the yield curve and their individual characteristics. Because the Company does not intend to sell these securities nor does the Company consider it more likely than not that it will be required to sell these securities before the recovery of amortized cost basis, which may be upon maturity, the Company concluded an allowance for credit losses is unnecessary at March 31, 2022.

At March 31, 2022, there were 433 state and municipal government securities in an unrealized loss position. The unrealized losses on state and municipal securities were caused by interest rate changes or widening of market spreads subsequent to the purchase of the individual securities. Management monitors published credit ratings of these securities for adverse changes. As of March 31, 2022, none of the rated obligations of state and local government entities held by the Company had a below investment grade credit rating. Because the credit quality of these securities are investment grade and the Company does not intend to sell these securities nor does the Company consider it more likely than not that it will be required to sell these securities before the recovery of amortized cost basis, which may be upon maturity, the Company concluded an allowance for credit losses is unnecessary at March 31, 2022.

At March 31, 2022, there were 12 U.S. government agency and government-sponsored enterprise securities in an unrealized loss position. The decline in fair value is attributable to changes in interest rates relative to where these investments fall within the yield curve and their individual characteristics. Because the Company does not intend to sell these securities nor does the Company consider it more likely than not that it will be required to sell these securities before the recovery of amortized cost basis, which may be upon maturity, the Company concluded an allowance for credit losses is unnecessary at March 31, 2022.

At March 31, 2022, there were 10 U.S. government securities in an unrealized loss position. The decline in fair value is attributable to changes in interest rates relative to where these investments fall within the yield curve and their individual characteristics. Because the Company does not intend to sell these securities nor does the Company consider it more likely than not that it will be required to sell these securities before the recovery of amortized cost basis, which may be upon maturity, the Company concluded an allowance for credit losses is unnecessary at March 31, 2022.

At March 31, 2022, there were 55 non-agency collateralized mortgage obligations in an unrealized loss position. The decline in fair value is attributable to changes in interest rates relative to where these investments fall within the yield curve and their individual characteristics. Because the Company does not intend to sell these securities nor does the Company consider it more likely than not that it will be required to sell these securities before the recovery of amortized cost basis, which may be upon maturity, the Company concluded an allowance for credit losses is unnecessary at March 31, 2022.