SECURITIES AND OTHER INVESTMENTS (Amortized Cost, Gross Unrealized Gains and Losses, and Estimated Fair Values of Investment Securities) (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Debt Securities, Available-for-sale Securities, Amortized Cost Basis [Abstract]
Total AFS securities	$ 2,844,763	$ 2,615,536
Gross Unrealized Gains	3,378	1,592
Gross Unrealized (Losses)	(405,975)	(385,867)
Total AFS securities, Estimated Fair Value	2,442,166	2,231,261
US Government Agencies Debt Securities [Member]
Debt Securities, Available-for-sale Securities, Amortized Cost Basis [Abstract]
Total AFS securities	65,650	62,367
Gross Unrealized Gains	390	1,023
Gross Unrealized (Losses)	(27)	(34)
Total AFS securities, Estimated Fair Value	66,013	63,356
US States and Political Subdivisions Debt Securities [Member]
Debt Securities, Available-for-sale Securities, Amortized Cost Basis [Abstract]
Total AFS securities	597,956	586,865
Gross Unrealized Gains	84	33
Gross Unrealized (Losses)	(129,703)	(111,451)
Total AFS securities, Estimated Fair Value	468,337	475,447
Corporate Bond Securities [Member]
Debt Securities, Available-for-sale Securities, Amortized Cost Basis [Abstract]
Total AFS securities	253,526	261,656
Gross Unrealized Gains	505	7
Gross Unrealized (Losses)	(9,319)	(19,774)
Total AFS securities, Estimated Fair Value	244,712	241,889
Commercial Mortgage-Backed Securities [Member]
Debt Securities, Available-for-sale Securities, Amortized Cost Basis [Abstract]
Total AFS securities	347,501	300,518
Gross Unrealized Gains	352	274
Gross Unrealized (Losses)	(46,788)	(43,146)
Total AFS securities, Estimated Fair Value	301,065	257,646
Commercial Mortgage-Backed Securities [Member] \| Agency Securities [Member]
Debt Securities, Available-for-sale Securities, Amortized Cost Basis [Abstract]
Total AFS securities	285,949	233,775
Gross Unrealized Gains	348	274
Gross Unrealized (Losses)	(44,678)	(41,181)
Total AFS securities, Estimated Fair Value	241,619	192,868
Commercial Mortgage-Backed Securities [Member] \| Non-agency
Debt Securities, Available-for-sale Securities, Amortized Cost Basis [Abstract]
Total AFS securities	61,552	66,743
Gross Unrealized Gains	4	0
Gross Unrealized (Losses)	(2,110)	(1,965)
Total AFS securities, Estimated Fair Value	59,446	64,778
Residential Mortgage-Backed Securities [Member]
Debt Securities, Available-for-sale Securities, Amortized Cost Basis [Abstract]
Total AFS securities	1,578,270	1,402,378
Gross Unrealized Gains	2,047	255
Gross Unrealized (Losses)	(220,138)	(211,462)
Total AFS securities, Estimated Fair Value	1,360,179	1,191,171
Residential Mortgage-Backed Securities [Member] \| Agency Securities [Member]
Debt Securities, Available-for-sale Securities, Amortized Cost Basis [Abstract]
Total AFS securities	1,478,648	1,312,538
Gross Unrealized Gains	1,375	114
Gross Unrealized (Losses)	(216,754)	(205,635)
Total AFS securities, Estimated Fair Value	1,263,269	1,107,017
Residential Mortgage-Backed Securities [Member] \| Non-agency
Debt Securities, Available-for-sale Securities, Amortized Cost Basis [Abstract]
Total AFS securities	99,622	89,840
Gross Unrealized Gains	672	141
Gross Unrealized (Losses)	(3,384)	(5,827)
Total AFS securities, Estimated Fair Value	96,910	84,154
Collateralized Securities, Other [Member]
Debt Securities, Available-for-sale Securities, Amortized Cost Basis [Abstract]
Total AFS securities	1,860	1,752
Gross Unrealized Gains	0	0
Gross Unrealized (Losses)	0	0
Total AFS securities, Estimated Fair Value	$ 1,860	$ 1,752

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

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- Definition

Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

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Amortized cost excluding accrued interest, before allowance for credit loss, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479130/326-30-45-1

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Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479130/326-30-45-1

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