DEPOSITS - Scheduled Maturities of Time Deposits (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Certificates of deposit of $250,000 or less
2020	$ 527,920
2021	46,186
2022	4,300
2023	2,795
2024	1,571
Total	582,772	$ 2,388,592
Certificates of deposit of more than $250,000
2020	578,583
2021	15,433
2022	26,442
2023	814
2024	0
Total	621,272	$ 809,282
Time Deposits [Abstract]
2020	1,106,503
2021	61,619
2022	30,742
2023	3,609
2024	1,571
Total	$ 1,204,044

Contractual Maturities, Time Deposits, $250,000 Or More [Abstract]

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Time Deposit Maturities Year Five And Thereafter

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Time Deposits $250,000 Maturities or More, Year Five and Thereafter

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Time Deposits $250,000 Maturities or More, Year Four

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Time Deposits $250,000 Maturities or More, Year One

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Time Deposits $250,000 Maturities or More, Year Three

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Time Deposits $250,000 Maturities or More, Year Two

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Time Deposits, $250,000 Or More

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Time Deposits, Less than $250,000

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Time Deposits Under $250,000 Maturities [Abstract]

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Time Deposits Under $100,000 Maturities, Year Five and Thereafter

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Time Deposits Under $250,000 Maturities, Year Four

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Time Deposits Under $250,000 Maturities, Year One

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Time Deposits Under $250,000 Maturities, Year Three

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Time Deposits Under $250,000 Maturities, Year Two

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Total Certificates Of Deposit [Abstract]

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Amount of time deposits maturing in the fourth fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section 50
-Paragraph 1
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Amount of time deposits maturing in the next fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of time deposits maturing in the third fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of time deposits maturing in the second fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of time deposit liabilities, including certificates of deposit.

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