DERIVATIVE INSTRUMENTS HEDGING AND NON-HEDGING ACTIVITIES - Fair Value and Notional Amounts (Details)	Dec. 31, 2017 USD ($) contract
Derivative Assets
Number of contracts \| contract	14,355
Fair value	$ 5,349,613
Notional	$ 14,355,000,000
Derivative Liabilities
Number of contracts \| contract	0
Fair value	$ 0
Notional	$ 0
Eurodollar Futures (Short positions)
Derivative Assets
Number of contracts \| contract	14,355
Fair value	$ 5,349,613
Notional	$ 14,355,000,000
Derivative Liabilities
Number of contracts \| contract	0
Fair value	$ 0
Notional	$ 0

Nominal or face amount used to calculate payments on the derivative asset.

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