FINANCIAL INSTRUMENTS Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value / carrying value	$ 17,724		$ 16,384
Income (loss) from equity method investments	$ 888	$ 431
AccuRisk Holdings LLC | Variable Interest Entity, Not Primary Beneficiary
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity method investment, ownership percentage	58.00%		58.00%
line of credit facility increase accrued interest	$ 6,000
Income (loss) from equity method investments	900	$ 400
Private investments and unlisted equity funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value / carrying value	11,134		$ 10,681
Other investments, accumulated gross unrealized holding gain (loss)	$ 800		$ 200