CONDENSED CONSOLIDATED STATEMENTS OF EQUITY (DEFICIT) - USD ($) shares in Thousands, $ in Thousands	Total	BAV	Sebago	Common Stock	Common Stock BAV	Common Stock Sebago	Additional Paid-in Capital	Additional Paid-in Capital BAV	Additional Paid-in Capital Sebago	Accumulated Deficit	Accumulated Other Comprehensive Income (Loss)	Treasury Stock	Noncontrolling Interests in Consolidated Entities	Convertible Preferred Stock	Redeemable Noncontrolling Interests
Beginning balance (in shares) at Dec. 31, 2018				2,392
Beginning balance at Dec. 31, 2018	$ 65,901			$ 24			$ 280,159			$ (214,242)	$ (498)		$ 458
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity-based compensation (in shares)				8
Equity-based compensation	6,901						6,917						(16)
Acquisitions (in shares)					60	135
Acquisitions		$ 3,748	$ 4,547		$ 1	$ 1		$ 3,747	$ 4,546
Investment in Real Estate Advisory Holdings LLC (in shares)				17
Investment in Real Estate Advisory Holdings LLC	887						887
Amortization of preferred stock discount	(1,338)									(1,338)				$ 1,338
Dividends declared and undeclared - preferred stock	(8,492)
Dividends declared - preferred stock	$ (8,492)									(8,492)
Deferred compensation plan distribution (in shares)	3			3
Deferred compensation plan distribution	$ 93						93
Employee advances	353						353
Contributions from noncontrolling interests	1,038												1,038
Reallocation of carrying value	(746)						(489)						(257)		$ 746
Redemption value adjustment	27									27					(27)
Distributions to consolidated noncontrolling interests	(63)												(63)
Foreign currency translation adjustment	105										105				14
Reclassification for realized loss (gain) on available for sale securities	0
Net income (loss)	(5,334)									(5,334)					(623)
Net income (loss)	(5,729)												(395)
Ending balance (in shares) at Sep. 30, 2019				2,615
Ending balance at Sep. 30, 2019	67,232			$ 26			296,213			(229,379)	(393)		765
Temporary equity, beginning balance (in shares) at Dec. 31, 2018														8,120
Temporary equity, beginning balance at Dec. 31, 2018														$ 200,847
Redeemable noncontrolling interests, beginning balance at Dec. 31, 2018															3,531
Increase (Decrease) in Temporary Equity [Roll Forward]
Amortization of preferred stock discount	(1,338)									(1,338)				$ 1,338
Reallocation of carrying value	(746)						(489)						(257)		746
Redemption value adjustment, year-to-date	27									27					(27)
Foreign currency translation adjustment	105										105				14
Net income (loss) attributable to the Company	(5,334)									(5,334)					(623)
Temporary equity, ending balance (in shares) at Sep. 30, 2019														8,120
Temporary equity, ending balance at Sep. 30, 2019														$ 202,185
Redeemable noncontrolling interests, ending balance at Sep. 30, 2019															3,641
Beginning balance (in shares) at Dec. 31, 2018				2,392
Beginning balance at Dec. 31, 2018	65,901			$ 24			280,159			(214,242)	(498)		458
Ending balance (in shares) at Dec. 31, 2019				2,203								2
Ending balance at Dec. 31, 2019	42,024			$ 2			285,825			(244,084)	(216)	$ (131)	628
Temporary equity, beginning balance (in shares) at Dec. 31, 2018														8,120
Temporary equity, beginning balance at Dec. 31, 2018														$ 200,847
Redeemable noncontrolling interests, beginning balance at Dec. 31, 2018															3,531
Temporary equity, ending balance (in shares) at Dec. 31, 2019														19,120
Temporary equity, ending balance at Dec. 31, 2019														$ 474,060
Redeemable noncontrolling interests, ending balance at Dec. 31, 2019	4,131														4,131
Beginning balance (in shares) at Jun. 30, 2019				2,476
Beginning balance at Jun. 30, 2019	69,998			$ 25			289,821			(219,965)	(293)		410
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity-based compensation (in shares)				3
Equity-based compensation	2,089						2,081						8
Acquisitions (in shares)					135
Acquisitions		$ 4,547			$ 1			$ 4,546
Amortization of preferred stock discount	(363)									(363)				$ 363
Dividends declared and undeclared - preferred stock	(2,909)
Dividends declared - preferred stock	$ (2,909)									(2,909)
Deferred compensation plan distribution (in shares)	1			1
Deferred compensation plan distribution	$ 20						20
Contributions from noncontrolling interests	583												583
Reallocation of carrying value	(390)						(255)						(135)		390
Redemption value adjustment	14									14					(14)
Foreign currency translation adjustment	(100)										(100)				(16)
Reclassification for realized loss (gain) on available for sale securities	0
Net income (loss)	(6,156)									(6,156)					(334)
Net income (loss)	(6,257)												(101)
Ending balance (in shares) at Sep. 30, 2019				2,615
Ending balance at Sep. 30, 2019	67,232			$ 26			296,213			(229,379)	(393)		765
Temporary equity, beginning balance (in shares) at Jun. 30, 2019														8,120
Temporary equity, beginning balance at Jun. 30, 2019														$ 201,822
Redeemable noncontrolling interests, beginning balance at Jun. 30, 2019															3,615
Increase (Decrease) in Temporary Equity [Roll Forward]
Amortization of preferred stock discount	(363)									(363)				$ 363
Reallocation of carrying value	(390)						(255)						(135)		390
Redemption value adjustment, year-to-date	14									14					(14)
Foreign currency translation adjustment	(100)										(100)				(16)
Net income (loss) attributable to the Company	(6,156)									(6,156)					(334)
Temporary equity, ending balance (in shares) at Sep. 30, 2019														8,120
Temporary equity, ending balance at Sep. 30, 2019														$ 202,185
Redeemable noncontrolling interests, ending balance at Sep. 30, 2019															3,641
Beginning balance (in shares) at Dec. 31, 2019				2,203								2
Beginning balance at Dec. 31, 2019	42,024			$ 2			285,825			(244,084)	(216)	$ (131)	628
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity-based compensation (in shares)				365
Equity-based compensation	4,516			$ 1			4,512						3
Forfeiture of restricted common shares (in shares)				(28)								(28)
Forfeiture of restricted common shares	0						287					$ (287)
Purchase of treasury stock (in shares)				(2)								(2)
Purchase of treasury stock	(18)											$ (18)
Amortization of preferred stock discount	(2,386)									(2,400)				$ 2,386
Dividends declared and undeclared - preferred stock	(23,800)									(23,800)
Dividends declared - preferred stock	$ (15,815)
Deferred compensation plan distribution (in shares)	1			1
Deferred compensation plan distribution	$ 8						8
Employee advances	79						79
Contributions from noncontrolling interests	457												457
Reallocation of carrying value	(56)						(37)						(19)		56
Redemption value adjustment	(528)									(528)					528
Foreign currency translation adjustment	(519)										(519)				(65)
Unrealized gain (loss) on available for sale securities	(1,014)										(1,014)
Reclassification for realized loss (gain) on available for sale securities	386										386
Net income (loss)	(198,853)									(198,853)					(1,688)
Net income (loss)	(199,610)												(757)
Ending balance (in shares) at Sep. 30, 2020				2,539								32
Ending balance at Sep. 30, 2020	(180,461)			$ 3			290,674			(469,651)	(1,363)	$ (436)	312
Temporary equity, beginning balance (in shares) at Dec. 31, 2019														19,120
Temporary equity, beginning balance at Dec. 31, 2019														$ 474,060
Redeemable noncontrolling interests, beginning balance at Dec. 31, 2019	4,131														4,131
Increase (Decrease) in Temporary Equity [Roll Forward]
Amortization of preferred stock discount	(2,386)									(2,400)				$ 2,386
Reallocation of carrying value	(56)						(37)						(19)		56
Redemption value adjustment, year-to-date	(528)									(528)					528
Foreign currency translation adjustment	(519)										(519)				(65)
Net income (loss) attributable to the Company	(198,853)									(198,853)					(1,688)
Temporary equity, ending balance (in shares) at Sep. 30, 2020														19,120
Temporary equity, ending balance at Sep. 30, 2020														$ 476,446
Redeemable noncontrolling interests, ending balance at Sep. 30, 2020	2,962														2,962
Beginning balance (in shares) at Jun. 30, 2020				2,505								31
Beginning balance at Jun. 30, 2020	(159,163)			$ 3			288,774			(447,649)	(114)	$ (428)	251
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity-based compensation (in shares)				35
Equity-based compensation	1,922						1,922
Forfeiture of restricted common shares (in shares)				(1)								(1)
Forfeiture of restricted common shares	0						7					$ (7)
Purchase of treasury stock	(1)											$ (1)
Amortization of preferred stock discount	(781)									(781)				$ 781
Dividends declared and undeclared - preferred stock	(7,985)									(7,985)
Dividends declared - preferred stock	$ (7,875)
Deferred compensation plan distribution (in shares)	0
Deferred compensation plan distribution	$ 2						2
Employee advances	(31)						(31)
Contributions from noncontrolling interests	380												380
Redemption value adjustment	(19)									(19)					19
Foreign currency translation adjustment	(1,035)										(1,035)				(135)
Unrealized gain (loss) on available for sale securities	(214)										(214)
Reclassification for realized loss (gain) on available for sale securities	0
Net income (loss)	(13,217)														(604)
Net income (loss)	(13,536)									(13,217)			(319)
Ending balance (in shares) at Sep. 30, 2020				2,539								32
Ending balance at Sep. 30, 2020	(180,461)			$ 3			$ 290,674			(469,651)	(1,363)	$ (436)	$ 312
Temporary equity, beginning balance (in shares) at Jun. 30, 2020														19,120
Temporary equity, beginning balance at Jun. 30, 2020														$ 475,665
Redeemable noncontrolling interests, beginning balance at Jun. 30, 2020															3,682
Increase (Decrease) in Temporary Equity [Roll Forward]
Amortization of preferred stock discount	(781)									(781)				$ 781
Redemption value adjustment, year-to-date	(19)									$ (19)					19
Foreign currency translation adjustment	(1,035)										$ (1,035)				(135)
Net income (loss) attributable to the Company	(13,217)														(604)
Temporary equity, ending balance (in shares) at Sep. 30, 2020														19,120
Temporary equity, ending balance at Sep. 30, 2020														$ 476,446
Redeemable noncontrolling interests, ending balance at Sep. 30, 2020	$ 2,962														$ 2,962