FAIR VALUE MEASUREMENTS - Narrative (Details) $ in Thousands	3 Months Ended		12 Months Ended
	Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2018 USD ($)
Guarantees of Farmers | Discounted Cash Flow Valuation Technique | Minimum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Market interest rate (as a percent)	15.00%
Guarantees of Farmers | Discounted Cash Flow Valuation Technique | Maximum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Market interest rate (as a percent)	35.00%
Securitized Beneficial Interests
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Unrealized losses for securitized beneficial interests	$ 801	$ 340	$ 2,531
Securitized Beneficial Interests | Minimum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Payment speed	82 days
Discount rate (as a percent)	3.50%
Securitized Beneficial Interests | Maximum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Payment speed		87 days
Discount rate (as a percent)		4.50%
Loss Severity | Guarantees of Farmers | Historical Loss Valuation Technique | Minimum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Historical loss (as a percent)	0.026
Loss Severity | Guarantees of Farmers | Historical Loss Valuation Technique | Maximum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Historical loss (as a percent)	0.100