Operating Segment Data Table of Segment Results (Details) $ in Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)		Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)
Segment Reporting, Disclosure of Entity's Reportable Segments [Abstract]
Number of Reportable Segments				4
Segment Reporting Information, Operating Income (Loss) [Abstract]
Total revenues	$ 157,870	$ 132,161		$ 321,778	$ 262,899
Total expenses	167,964	126,027		333,279	252,895
Net income (loss) attributable to consolidated CLOs	2,895	4,912		6,810	6,017
Pre-tax income (loss)	(7,199)	11,046		(4,691)	16,021
Less: provision (benefit) for income taxes	(1,875)	4,025		(709)	1,586
Net income (loss) before non-controlling interests	(5,324)	7,021		(3,982)	14,435
Net income (loss) available to common stockholders	(4,443)	6,133		(3,343)	11,688
Asset Management Segment
Segment Reporting Information, Operating Income (Loss) [Abstract]
Total revenues	3,818	2,228		6,791	6,008	[1]
Total expenses	2,184	1,647		3,491	3,828	[1]
Net income (loss) attributable to consolidated CLOs	2,895	4,912		6,810	6,017	[1]
Pre-tax income (loss)	4,529	5,493		10,110	8,197	[1]
Senior Living Segment
Segment Reporting Information, Operating Income (Loss) [Abstract]
Total revenues	18,625	14,619		36,344	28,509
Total expenses	20,919	15,774		40,168	33,523
Net income (loss) attributable to consolidated CLOs	0	0		0	0
Pre-tax income (loss)	(2,294)	(1,155)		(3,824)	(5,014)
Specialty Finance Segment
Segment Reporting Information, Operating Income (Loss) [Abstract]
Total revenues	23,896	22,211		45,349	38,777
Total expenses	24,330	19,899		45,315	37,448
Net income (loss) attributable to consolidated CLOs	0	0		0	0
Pre-tax income (loss)	(434)	2,312		34	1,329
Corporate And Eliminations
Segment Reporting Information, Operating Income (Loss) [Abstract]
Total revenues	360	96	[1]	277	3,492	[1]
Total expenses	8,628	8,465	[1]	15,357	16,951	[1]
Net income (loss) attributable to consolidated CLOs	0	0	[1]	0	0
Pre-tax income (loss)	(8,268)	(8,369)	[1]	(15,080)	(13,459)	[1]
Specialty Insurance
Segment Reporting Information, Operating Income (Loss) [Abstract]
Total revenues	111,171	93,007		233,017	186,113	[1]
Total expenses	111,903	80,242		228,948	161,145	[1]
Net income (loss) attributable to consolidated CLOs	0	0		0	0
Pre-tax income (loss)	(732)	12,765		4,069	24,968	[1]
Noncontrolling interest
Segment Reporting Information, Operating Income (Loss) [Abstract]
Less: net (loss) income attributable to non-controlling interests	$ (881)	888		$ (639)	2,747
Scenario, Adjustment | Reclassifications | Asset Management Segment
Segment Reporting Information, Operating Income (Loss) [Abstract]
Net income (loss) attributable to consolidated CLOs		4,166			4,271
Pre-tax income (loss)		4,415			5,459
Scenario, Adjustment | Reclassifications | Specialty Insurance
Segment Reporting Information, Operating Income (Loss) [Abstract]
Pre-tax income (loss)		$ 4,687			$ 7,893

[1] (1) Reclassified to conform to current period presentation