OFFSETTING ASSETS AND LIABILITIES - Offsetting Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Derivatives
Net amounts of liabilities presented in the balance sheet	$ 0	$ 0
Repurchase agreements
Gross amounts of recognized liabilities	1,726,800	1,815,934
Gross amounts offset in the balance sheet	0	0
Net amounts of liabilities presented in the balance sheet	1,726,800	1,815,934
Gross amounts not offset in the balance sheet
Financial instruments collateral	1,726,800	1,815,934
Cash collateral posted/(received)	0	0
Net amount	0	0
Total
Gross amounts of recognized liabilities	1,726,800	1,815,934
Gross amounts offset in the balance sheet	0	0
Net amounts of liabilities presented in the balance sheet	1,726,800	1,815,934
Gross amounts not offset in the balance sheet
Financial instruments collateral	1,726,800	1,815,934
Cash collateral posted/(received)	0	0
Net amount	$ 0	$ 0

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