COMMITMENTS AND CONTINGENCIES Lease (Details) $ in Thousands, € in Millions		3 Months Ended			9 Months Ended
		Sep. 30, 2017 USD ($)		Sep. 30, 2016 USD ($)	Sep. 30, 2017 USD ($)		Sep. 30, 2017 EUR (€)	Sep. 30, 2016 USD ($)	Dec. 31, 2016 USD ($)
Operating Leased Assets [Line Items]
Total rent expense related to leased office space		$ 200		$ 100	$ 500			$ 400
Operating Lease obligations, 2017		154			154
Operating lease obligations, 2018		388			388
Operating lease obligations, 2019		155			155
Operating lease obligations, 2020		155			155
Operating lease obligations, 2021		58			58
Operating lease obligations, Thereafter		0			0
Operating lease obligations, Total		910			910
Contractual Obligations Total 2017		7,368			7,368
Contractual Obligations Total 2018		388			388
Contractual Obligations Total 2019		155			155
Contractual Obligations Total 2020		155			155
Contractual Obligations Total 2021		58			58
Contractual Obligations Total, Thereafter		0			0
Contractual Obligations Total		8,124			$ 8,124
GLRE
Operating Leased Assets [Line Items]
Operating lease renewal option					5 years		5 years
GLRE | Minimum
Operating Leased Assets [Line Items]
Annual rent payments					$ 300
GLRE | Maximum
Operating Leased Assets [Line Items]
Annual rent payments					500
GRIL
Operating Leased Assets [Line Items]
Annual rent payments | €							€ 0.1
Private equity and limited partnerships (1)
Operating Leased Assets [Line Items]
Unrecorded Unconditional Purchase Obligation, Due in Next Twelve Months		7,214	[1]		7,214	[1]			$ 9,200
Unrecorded Unconditional Purchase Obligation, Due within Two Years	[1]	0			0
Unrecorded Unconditional Purchase Obligation, Due within Three Years	[1]	0			0
Unrecorded Unconditional Purchase Obligation, Due within Four Years	[1]	0			0
Unrecorded Unconditional Purchase Obligation, Due within Five Years	[1]	0			0
Unrecorded Unconditional Purchase Obligation, Due after Five Years	[1]	0			0
Unrecorded Unconditional Purchase Obligation	[1]	$ 7,214			$ 7,214

[1] Given the nature of these investments, the Company is unable to determine with any degree of accuracy when these commitments will be called. Therefore, for purposes of the above table, the Company has assumed that all commitments with no fixed payment schedules will be called during the year ending December 31, 2017