LOANS - Corporate Debt Amortized Costs Basis by Risk Rating and Vintage Year (Details) - Corporate Loans $ in Thousands	Jun. 30, 2020 USD ($)
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Total	$ 2,185,777
2020	275,139
2019	514,428
2018	844,838
2017	384,878
2016	116,915
2015	34,048
Revolvers	15,531
Accrued interest receivable	11,400
Performing
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Total	1,613,987
2020	275,139
2019	413,306
2018	503,077
2017	301,941
2016	72,187
2015	34,048
Revolvers	14,289
Special Mention
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Total	382,619
2020	0
2019	77,211
2018	221,072
2017	38,366
2016	44,728
2015	0
Revolvers	1,242
Substandard
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Total	172,548
2020	0
2019	23,911
2018	108,333
2017	40,304
2016	0
2015	0
Revolvers	0
Doubtful
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Total	16,623
2020	0
2019	0
2018	12,356
2017	4,267
2016	0
2015	0
Revolvers	0
Loss
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Total	0
2020	0
2019	0
2018	0
2017	0
2016	0
2015	0
Revolvers	$ 0

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Debt Securities, Held-to-maturity, before Allowance for Credit Loss

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Amount of investment in debt security measured at amortized cost (held-to-maturity), originated five or more years prior to latest fiscal year.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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-Publisher FASB
-Name Accounting Standards Codification
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