Note 4 - Investment Securities (Tables)

6 Months Ended

Jun. 30, 2026

Notes Tables

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

		*June 30, 2026*
						*Gross*				*Gross*
		*Amortized*				*Unrealized*				*Unrealized*
		*Cost*				*Gains*				*Losses*				*Fair Value*
		($ In thousands)
Securities AFS
U.S. treasury securities		$	936,776			$	—			$	312			$	936,464
U.S. government agency entities			1,102				50				107				1,045
Mortgage-backed securities			723,516				282				52,945				670,853
Collateralized mortgage obligations			5,818				—				1,194				4,624
Corporate debt securities			70,000				50				216				69,834
Total		$	1,737,212			$	382			$	54,774			$	1,682,820

		*December 31, 2025*
						*Gross*				*Gross*
		*Amortized*				*Unrealized*				*Unrealized*
		*Cost*				*Gains*				*Losses*				*Fair Value*
		($ In thousands)
Securities AFS
U.S. treasury securities		$	827,763			$	430			$	—			$	828,193
U.S. government agency entities			5,888				52				118				5,822
U.S. government sponsored entities			25,000				11				—				25,011
Mortgage-backed securities			704,213				548				75,324				629,437
Collateralized mortgage obligations			24,454				—				1,706				22,748
Corporate debt securities			148,133				101				1,222				147,012
Total		$	1,735,451			$	1,142			$	78,370			$	1,658,223

Investments Classified by Contractual Maturity Date [Table Text Block]

		*June 30, 2026*
		*Securities AFS*
		*Amortized Cost*				*Fair Value*
		($ In thousands)

Due in one year or less		$	991,877			$	991,260
Due after one year through five years			15,336				15,382
Due after five years through ten years			1,649				1,428
Due after ten years			728,350				674,750
Total		$	1,737,212			$	1,682,820

Unrealized Gain (Loss) on Investments [Table Text Block]

		*June 30, 2026*
		*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 AFS
U.S. treasury securities		$	936,464			$	312			$	—			$	—			$	936,464			$	312
U.S. government agency entities			—				—				979				107				979				107
Mortgage-backed securities			342,113				1,623				295,958				51,322				638,071				52,945
Collateralized mortgage obligations			—				—				4,624				1,194				4,624				1,194
Corporate debt securities			—				—				54,784				216				54,784				216
Total		$	1,278,577			$	1,935			$	356,345			$	52,839			$	1,634,922			$	54,774

		*December 31, 2025*
		*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 AFS
U.S. government agency entities		$	834			$	1			$	3,585			$	117			$	4,419			$	118
Mortgage-backed securities			207				—				600,658				75,324				600,865				75,324
Collateralized mortgage obligations			—				—				22,747				1,706				22,747				1,706
Corporate debt securities			—				—				76,912				1,222				76,912				1,222
Total		$	1,041			$	1			$	703,902			$	78,369			$	704,943			$	78,370