Revenues - Disaggregated Revenue (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($) segment	Sep. 30, 2019 USD ($)
Revenue from External Customer [Line Items]
Total revenues	$ 55,868	$ 56,889	$ 235,308	$ 183,675
Number of reportable segments | segment			5
Advisory services
Revenue from External Customer [Line Items]
Total revenues	10,832	10,871	$ 34,098	33,280
Base advisory fee
Revenue from External Customer [Line Items]
Total revenues	11,040	10,570	33,707	32,382
Incentive advisory fee
Revenue from External Customer [Line Items]
Total revenues	(339)	170	0	509
Other advisory revenue
Revenue from External Customer [Line Items]
Total revenues	131	131	391	389
Base fee
Revenue from External Customer [Line Items]
Total revenues	3,777	0	13,592	0
Project management fees
Revenue from External Customer [Line Items]
Total revenues	1,790	6,660	7,780	19,533
Audio visual
Revenue from External Customer [Line Items]
Total revenues	3,114	22,430	33,758	83,532
Total other revenue
Revenue from External Customer [Line Items]
Total revenues	8,222	5,627	18,250	14,719
Debt placement and related fees
Revenue from External Customer [Line Items]
Total revenues	4,017	429	5,480	1,862
Claims management services
Revenue from External Customer [Line Items]
Total revenues	55	51	184	147
Lease revenue
Revenue from External Customer [Line Items]
Total revenues	0	1,029	0	3,088
Other services
Revenue from External Customer [Line Items]
Total revenues	4,150	4,118	12,586	9,622
Cost reimbursement revenue
Revenue from External Customer [Line Items]
Total revenues	28,133	11,301	127,830	32,611
JSAV
Revenue from External Customer [Line Items]
Total revenues	3,114	22,430	33,758	83,532
Operating Segments | REIT Advisory
Revenue from External Customer [Line Items]
Total revenues	16,790	21,381	53,297	64,638
Operating Segments | REIT Advisory | Advisory services
Revenue from External Customer [Line Items]
Total revenues	10,832	10,871	34,098	33,280
Operating Segments | REIT Advisory | Project management fees
Revenue from External Customer [Line Items]
Total revenues	0	0	0	0
Operating Segments | REIT Advisory | Audio visual
Revenue from External Customer [Line Items]
Total revenues	0	0	0	0
Operating Segments | REIT Advisory | Cost reimbursement revenue
Revenue from External Customer [Line Items]
Total revenues	5,903	9,430	19,004	28,123
Operating Segments | Remington
Revenue from External Customer [Line Items]
Total revenues	24,800	0	117,715	0
Operating Segments | Remington | Advisory services
Revenue from External Customer [Line Items]
Total revenues	0		0
Operating Segments | Remington | Project management fees
Revenue from External Customer [Line Items]
Total revenues	0		0
Operating Segments | Remington | Audio visual
Revenue from External Customer [Line Items]
Total revenues	0		0
Operating Segments | Remington | Cost reimbursement revenue
Revenue from External Customer [Line Items]
Total revenues	21,023		104,123
Operating Segments | Premier
Revenue from External Customer [Line Items]
Total revenues	2,277	7,881	10,173	23,371
Operating Segments | Premier | Advisory services
Revenue from External Customer [Line Items]
Total revenues	0	0	0	0
Operating Segments | Premier | Project management fees
Revenue from External Customer [Line Items]
Total revenues	1,790	6,660	7,780	19,533
Operating Segments | Premier | Audio visual
Revenue from External Customer [Line Items]
Total revenues	0	0	0	0
Operating Segments | Premier | Cost reimbursement revenue
Revenue from External Customer [Line Items]
Total revenues	487	1,221	2,393	3,838
Operating Segments | JSAV
Revenue from External Customer [Line Items]
Total revenues	3,114	22,430	33,758	83,532
Operating Segments | JSAV | Advisory services
Revenue from External Customer [Line Items]
Total revenues	0	0	0	0
Operating Segments | JSAV | Project management fees
Revenue from External Customer [Line Items]
Total revenues	0	0	0	0
Operating Segments | JSAV | Audio visual
Revenue from External Customer [Line Items]
Total revenues	3,114	22,430	33,758	83,532
Operating Segments | JSAV | Cost reimbursement revenue
Revenue from External Customer [Line Items]
Total revenues	0	0	0	0
Operating Segments | OpenKey
Revenue from External Customer [Line Items]
Total revenues	341	313	1,155	764
Operating Segments | OpenKey | Advisory services
Revenue from External Customer [Line Items]
Total revenues	0	0	0	0
Operating Segments | OpenKey | Project management fees
Revenue from External Customer [Line Items]
Total revenues	0	0	0	0
Operating Segments | OpenKey | Audio visual
Revenue from External Customer [Line Items]
Total revenues	0	0	0	0
Operating Segments | OpenKey | Cost reimbursement revenue
Revenue from External Customer [Line Items]
Total revenues	0	0	0	0
Corporate and Other
Revenue from External Customer [Line Items]
Total revenues	8,546	4,884	19,210	11,370
Corporate and Other | Advisory services
Revenue from External Customer [Line Items]
Total revenues	0	0	0	0
Corporate and Other | Project management fees
Revenue from External Customer [Line Items]
Total revenues	0	0	0	0
Corporate and Other | Audio visual
Revenue from External Customer [Line Items]
Total revenues	0	0	0	0
Corporate and Other | Cost reimbursement revenue
Revenue from External Customer [Line Items]
Total revenues	$ 720	$ 650	$ 2,310	$ 650