Note 8 - Investment Securities (Tables)

3 Months Ended

Mar. 31, 2022

Notes Tables

Schedule of Available-for-Sale Securities Reconciliation [Table Text Block]

	March 31, 2022
			Gross		Gross
	Amortized		Unrealized		Unrealized
	Cost		Gains		Losses		Fair Value
	(In thousands)
Securities Available-for-Sale
U.S. treasury securities	$	119,757	$	4	$	13	$	119,748
U.S. government agency entities		82,300		1,050		134		83,216
Mortgage-backed securities		929,428		521		56,444		873,505
Collateralized mortgage obligations		9,282		—		894		8,388
Corporate debt securities		144,096		50		9,462		134,684
Total	$	1,284,863	$	1,625	$	66,947	$	1,219,541

	December 31, 2021
			Gross		Gross
	Amortized		Unrealized		Unrealized
	Cost		Gains		Losses		Fair Value
	(In thousands)
Securities Available-for-Sale
U.S. government agency entities		86,475		1,169		135		87,509
Mortgage-backed securities		886,614		9,465		7,414		888,665
Collateralized mortgage obligations		9,547		—		430		9,117
Corporate debt securities		144,231		441		2,654		142,018
Total	$	1,126,867	$	11,075	$	10,633	$	1,127,309

Investments Classified by Contractual Maturity Date [Table Text Block]

	March 31, 2022
	Securities Available-For-Sale
	Amortized Cost		Fair Value
	(In thousands)
Due in one year or less	$	124,789	$	124,794
Due after one year through five years		126,637		117,089
Due after five years through ten years		142,206		141,424
Due after ten years		891,231		836,234
Total	$	1,284,863	$	1,219,541

Schedule of Unrealized Loss on Investments [Table Text Block]

	March 31, 2022
	Less than 12 Months				12 Months or Longer				Total
			Gross				Gross				Gross
	Fair		Unrealized		Fair		Unrealized		Fair		Unrealized
	Value		Losses		Value		Losses		Value		Losses
	(In thousands)
Securities Available-for-Sale
U.S. treasury securities	$	39,603	$	13	$	—	$	—	$	39,603	$	13
U.S. government agency entities		—		—		2,221		134		2,221		134
Mortgage-backed securities		695,157		40,532		144,040		15,912		839,197		56,444
Collateralized mortgage obligations		8,274		879		114		15		8,388		894
Corporate debt securities		102,960		7,858		18,396		1,604		121,356		9,462
Total	$	845,994	$	49,282	$	164,771	$	17,665	$	1,010,765	$	66,947

	December 31, 2021
	Less than 12 Months				12 Months or Longer				Total
			Gross				Gross				Gross
	Fair		Unrealized		Fair		Unrealized		Fair		Unrealized
	Value		Losses		Value		Losses		Value		Losses
	(In thousands)
Securities Available-for-Sale
U.S. government agency entities		—		—		2,337		135		2,337		135
Mortgage-backed securities		527,276		6,659		6,496		755		533,772		7,414
Collateralized mortgage obligations		8,989		417		128		13		9,117		430
Corporate debt securities		103,720		2,122		19,468		532		123,188		2,654
Total	$	639,985	$	9,198	$	28,429	$	1,435	$	668,414	$	10,633