Restructuring Charges - Changes to Restructuring Liability by Major Restructuring Activity (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Restructuring Cost And Reserve [Line Items]
Beginning balance		$ 3,435	$ 5,230	$ 4,513
Restructuring charges		3,059	6,066	13,440
Cash payments		(1,934)	(5,899)	(10,825)
Non-cash items	[1]	(1,167)	(1,906)	(1,789)
Adjustment to liability		46	(56)	(109)
Ending balance		3,439	3,435	5,230
GES | Severance & Employee Benefits
Restructuring Cost And Reserve [Line Items]
Beginning balance		1,976	2,440	2,935
Restructuring charges		624	1,829	6,563
Cash payments		(988)	(2,302)	(7,051)
Non-cash items	[1]	0	0	0
Adjustment to liability		(3)	9	(7)
Ending balance		1,609	1,976	2,440
GES | Facilities
Restructuring Cost And Reserve [Line Items]
Beginning balance		1,433	2,766	1,339
Restructuring charges		2,351	4,107	5,784
Cash payments		(863)	(3,506)	(2,573)
Non-cash items	[1]	(1,167)	(1,906)	(1,789)
Adjustment to liability		64	(28)	5
Ending balance		1,818	1,433	2,766
Other Restructuring | Severance & Employee Benefits
Restructuring Cost And Reserve [Line Items]
Beginning balance		26	24	239
Restructuring charges		84	130	1,093
Cash payments		(83)	(91)	(1,201)
Non-cash items	[1]	0	0	0
Adjustment to liability		(15)	(37)	(107)
Ending balance		$ 12	$ 26	$ 24

[1] Represents non-cash adjustments related to a write-down of certain ROU assets and leasehold improvements as a result of vacating certain facilities prior to the lease term during the year ended December 31, 2022, a write down of certain ROU assets as a result of vacating certain facilities prior to the lease term during the year ended December 31, 2021, and the closure and liquidation of GES’ United Kingdom-based audio-visual services business during the year ended December 31, 2020.