DEPOSITS AND RELATED INTEREST (Maturities of Time Deposits) (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Year-end amount, Within One Year
Three months or less	$ 430,860	$ 645,919
Over 3 months through 6 months	425,766	293,693
Over 6 months through 1 year	756,832	492,799
Within one year	1,613,458	1,432,411
Year-end amount, after one year:
Over 1 through 2 years	258,977	340,176
Over 2 through 3 years	69,228	63,044
Over 3 through 4 years	30,728	39,462
Over 4 through 5 years	31,697	33,549
Over 5 years	189	722
Certificates of deposit	2,004,277	1,909,364
Uninsured amount, within one year:
Three months or less	220,143	336,912
Over 3 months through 6 months	250,982	99,596
Over 6 months through 1 year	265,447	201,877
Within one year	736,572	638,385
Uninsured amount, after one year:
Over 1 through 2 years	53,408	95,690
Over 2 through 3 years	4,666	9,017
Over 3 through 4 years	4,237	4,176
Over 4 through 5 years	4,360	4,084
Over 5 years	0	115
Uninsured amount	$ 803,243	$ 751,467

Time Deposit Liability, Uninsured, Maturity Year One

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- Definition

Time Deposit Maturities Less Than Three Month

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- Definition

Time Deposit Maturities, Over Six Months Through Twelve Months

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- Definition

Time Deposit Maturities, Over Three Months Through Six Months

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- Definition

Over 5 years

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No definition available.

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- Definition

Over 4 through 5 years

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No definition available.

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Over 3 through 4 years

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Over 2 through 3 years

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Over 1 through 2 years

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- Definition

Total Time Deposits Excluding Equity Indexes Options

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- Definition

Uninsured Amount, After One Year

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Uninsured Amount, Within One Year

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Year-End Amount, After One Year

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Year-End Amount, Within One Year

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- Definition

Amount of uninsured time deposit liability. Excludes uninsured time deposit liability in excess of Federal Deposit Insurance Corporation (FDIC) insurance limit or similar state deposit insurance regime in United States of America (US).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1406
-Paragraph f
-Subparagraph (2)
-Publisher SEC

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Amount of uninsured time deposit liability with time remaining to mature over six through twelve months. Excludes uninsured time deposit liability in excess of Federal Deposit Insurance Corporation (FDIC) insurance limit or similar state deposit insurance regime in United States of America (US).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1406
-Paragraph f
-Subparagraph (2)(iii)
-Publisher SEC

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Amount of uninsured time deposit liability with time remaining to mature over three through six months. Excludes uninsured time deposit liability in excess of Federal Deposit Insurance Corporation (FDIC) insurance limit or similar state deposit insurance regime in United States of America (US).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1406
-Paragraph f
-Subparagraph (2)(ii)
-Publisher SEC

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Amount of uninsured time deposit liability with time remaining to mature in three months or less. Excludes uninsured time deposit liability in excess of Federal Deposit Insurance Corporation (FDIC) insurance limit or similar state deposit insurance regime in United States of America (US).

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1406
-Paragraph f
-Subparagraph (2)(i)
-Publisher SEC

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Amount of time deposit maturing after fifth fiscal year following current fiscal year. Time deposit includes, but is not limited to, certificate of deposit. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-SubTopic 10
-Topic 470
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481544/470-10-50-1

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Amount of time deposit maturing in fifth fiscal year following current fiscal year. Time deposit includes, but is not limited to, certificate of deposit. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of time deposit maturing in fourth fiscal year following current fiscal year. Time deposit includes, but is not limited to, certificate of deposit. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of time deposit maturing in next fiscal year following current fiscal year. Time deposit includes, but is not limited to, certificate of deposit. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of time deposit maturing in third fiscal year following current fiscal year. Time deposit includes, but is not limited to, certificate of deposit. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of time deposit maturing in second fiscal year following current fiscal year. Time deposit includes, but is not limited to, certificate of deposit. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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