DEPOSITS AND RELATED INTEREST (Maturities of Time Deposits) (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Year-end amount, Within One Year
Three months or less	$ 1,077,290	$ 751,849
Over 3 months through 6 months	608,115	430,578
Over 6 months through 1 year	746,136	628,006
Within one year	2,431,541	1,810,433
Year-end amount, after one year:
Over 1 through 2 years	180,708	255,528
Over 2 through 3 years	61,706	70,597
Over 3 through 4 years	26,643	28,586
Over 4 through 5 years	32,211	32,186
Over 5 years	16	28
Certificates of deposit	2,732,825	2,197,358
Uninsured amount, within one year:
Three months or less	644,156	369,112
Over 3 months through 6 months	440,716	166,044
Over 6 months through 1 year	306,934	243,192
Within one year	1,391,806	778,348
Uninsured amount, after one year:
Over 1 through 2 years	37,849	49,932
Over 2 through 3 years	5,587	6,470
Over 3 through 4 years	4,857	3,738
Over 4 through 5 years	3,501	4,251
Over 5 years	0	0
Uninsured amount	$ 1,443,600	$ 842,739

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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- Definition

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).

+ References

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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- Definition

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).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 942
-SubTopic 405
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478353/942-405-50-1

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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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