Revenue and Related Contract Costs and Contract Liabilities - Disaggregate GES and Pursuit Revenue by Major Product Line Timing of Revenue Recognition and Markets Served (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Disaggregation Of Revenue [Line Items]
Total revenue		$ 415,435	$ 1,302,736	$ 1,237,324
GES
Disaggregation Of Revenue [Line Items]
Total revenue		338,625	1,079,923	1,052,037
GES | Operating Segments
Disaggregation Of Revenue [Line Items]
Total revenue		338,625	1,079,923	1,052,037
GES | Intersegment Eliminations
Disaggregation Of Revenue [Line Items]
Total revenue		(3,680)	(20,741)	(17,140)
Pursuit
Disaggregation Of Revenue [Line Items]
Total revenue		76,810	222,813	185,287
Pursuit | Operating Segments
Disaggregation Of Revenue [Line Items]
Total revenue		76,810	222,813	185,287
Pursuit | Intersegment Eliminations
Disaggregation Of Revenue [Line Items]
Total revenue		(317)	(1,686)	(1,551)
North America | GES | Operating Segments
Disaggregation Of Revenue [Line Items]
Total revenue		288,921	884,105	866,187
EMEA | GES | Operating Segments
Disaggregation Of Revenue [Line Items]
Total revenue		53,384	216,559	202,990
Services Transferred Over Time | GES
Disaggregation Of Revenue [Line Items]
Total revenue		298,945	936,604	913,986
Services Transferred Over Time | GES | Intersegment Eliminations
Disaggregation Of Revenue [Line Items]
Total revenue		(3,680)	(20,741)	(17,140)
Services Transferred Over Time | Pursuit
Disaggregation Of Revenue [Line Items]
Total revenue		52,583	164,930	137,404
Services Transferred Over Time | North America | GES | Operating Segments
Disaggregation Of Revenue [Line Items]
Total revenue		260,964	809,499	793,343
Services Transferred Over Time | EMEA | GES | Operating Segments
Disaggregation Of Revenue [Line Items]
Total revenue		41,661	147,846	137,783
Products Transferred Over Time | GES
Disaggregation Of Revenue [Line Items]
Total revenue	[1]	15,517	61,668	60,193
Products Transferred Over Time | North America | GES | Operating Segments
Disaggregation Of Revenue [Line Items]
Total revenue	[1]	13,068	45,597	44,109
Products Transferred Over Time | EMEA | GES | Operating Segments
Disaggregation Of Revenue [Line Items]
Total revenue	[1]	2,449	16,071	16,084
Products Transferred at a Point in Time | GES
Disaggregation Of Revenue [Line Items]
Total revenue		24,163	81,651	77,858
Products Transferred at a Point in Time | Pursuit
Disaggregation Of Revenue [Line Items]
Total revenue		24,227	57,883	47,883
Products Transferred at a Point in Time | North America | GES | Operating Segments
Disaggregation Of Revenue [Line Items]
Total revenue		14,889	29,009	28,735
Products Transferred at a Point in Time | EMEA | GES | Operating Segments
Disaggregation Of Revenue [Line Items]
Total revenue		9,274	52,642	49,123
Core Services | GES
Disaggregation Of Revenue [Line Items]
Total revenue		265,222	815,621	794,918
Core Services | North America | GES | Operating Segments
Disaggregation Of Revenue [Line Items]
Total revenue		231,666	701,721	689,804
Core Services | EMEA | GES | Operating Segments
Disaggregation Of Revenue [Line Items]
Total revenue		33,556	113,900	105,114
Audio Visual | GES
Disaggregation Of Revenue [Line Items]
Total revenue		24,274	102,375	95,342
Audio Visual | North America | GES | Operating Segments
Disaggregation Of Revenue [Line Items]
Total revenue		20,148	78,178	73,331
Audio Visual | EMEA | GES | Operating Segments
Disaggregation Of Revenue [Line Items]
Total revenue		4,126	24,197	22,011
Event Technology | GES
Disaggregation Of Revenue [Line Items]
Total revenue		13,129	39,349	40,866
Event Technology | North America | GES | Operating Segments
Disaggregation Of Revenue [Line Items]
Total revenue		9,150	29,600	30,208
Event Technology | EMEA | GES | Operating Segments
Disaggregation Of Revenue [Line Items]
Total revenue		3,979	9,749	10,658
Total Services | GES
Disaggregation Of Revenue [Line Items]
Total revenue		298,945	936,604	913,986
Total Services | GES | Intersegment Eliminations
Disaggregation Of Revenue [Line Items]
Total revenue		(3,680)	(20,741)	(17,140)
Total Services | Pursuit
Disaggregation Of Revenue [Line Items]
Total revenue		52,583	164,930	137,404
Total Services | North America | GES | Operating Segments
Disaggregation Of Revenue [Line Items]
Total revenue		260,964	809,499	793,343
Total Services | EMEA | GES | Operating Segments
Disaggregation Of Revenue [Line Items]
Total revenue		41,661	147,846	137,783
Core Products | GES
Disaggregation Of Revenue [Line Items]
Total revenue		39,680	143,319	138,051
Core Products | North America | GES | Operating Segments
Disaggregation Of Revenue [Line Items]
Total revenue		27,957	74,606	72,844
Core Products | EMEA | GES | Operating Segments
Disaggregation Of Revenue [Line Items]
Total revenue		11,723	68,713	65,207
Exhibitions | GES
Disaggregation Of Revenue [Line Items]
Total revenue		252,030	623,050	635,738
Exhibitions | North America | GES | Operating Segments
Disaggregation Of Revenue [Line Items]
Total revenue		211,953	463,653	486,400
Exhibitions | EMEA | GES | Operating Segments
Disaggregation Of Revenue [Line Items]
Total revenue		40,077	159,397	149,338
Conferences | GES
Disaggregation Of Revenue [Line Items]
Total revenue		49,160	278,010	247,305
Conferences | North America | GES | Operating Segments
Disaggregation Of Revenue [Line Items]
Total revenue		41,371	253,511	223,096
Conferences | EMEA | GES | Operating Segments
Disaggregation Of Revenue [Line Items]
Total revenue		7,789	24,499	24,209
Corporate Events | GES
Disaggregation Of Revenue [Line Items]
Total revenue		29,874	171,562	153,497
Corporate Events | North America | GES | Operating Segments
Disaggregation Of Revenue [Line Items]
Total revenue		24,521	139,935	126,084
Corporate Events | EMEA | GES | Operating Segments
Disaggregation Of Revenue [Line Items]
Total revenue		5,353	31,627	27,413
Consumer Events | GES
Disaggregation Of Revenue [Line Items]
Total revenue		11,241	28,042	32,637
Consumer Events | North America | GES | Operating Segments
Disaggregation Of Revenue [Line Items]
Total revenue		11,076	27,006	30,607
Consumer Events | EMEA | GES | Operating Segments
Disaggregation Of Revenue [Line Items]
Total revenue		165	1,036	2,030
Admissions | Pursuit
Disaggregation Of Revenue [Line Items]
Total revenue		19,939	85,371	83,000
Accommodations | Pursuit
Disaggregation Of Revenue [Line Items]
Total revenue		29,800	60,672	37,470
Transportation | Pursuit
Disaggregation Of Revenue [Line Items]
Total revenue		2,694	14,594	13,956
Travel Planning | Pursuit
Disaggregation Of Revenue [Line Items]
Total revenue		467	5,979	4,529
Food and Beverage | Pursuit
Disaggregation Of Revenue [Line Items]
Total revenue		10,295	31,838	25,962
Retail Operations | Pursuit
Disaggregation Of Revenue [Line Items]
Total revenue		13,932	26,045	21,921
Products
Disaggregation Of Revenue [Line Items]
Total revenue		63,907	201,202	185,935
Products | Pursuit
Disaggregation Of Revenue [Line Items]
Total revenue		24,227	57,883	47,883
Banff Jasper Collection | Pursuit
Disaggregation Of Revenue [Line Items]
Total revenue		46,913	133,229	106,106
Alaska Collection | Pursuit
Disaggregation Of Revenue [Line Items]
Total revenue		6,282	39,406	36,451
Glacier Park Collection | Pursuit
Disaggregation Of Revenue [Line Items]
Total revenue		17,596	37,121	31,465
FlyOver | Pursuit
Disaggregation Of Revenue [Line Items]
Total revenue		$ 6,019	$ 13,057	$ 11,265

[1] GES’ graphics product revenue is earned over time over the duration of an event as it is considered a part of the single performance obligation satisfied over time.