Segment Information - Reconciliation of Income Statement Items from Reportable Segments (Details) - USD ($) $ in Thousands		3 Months Ended								12 Months Ended
		Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Reportable segments reconciliations:
Total revenue		$ 277,285	$ 339,099	$ 364,774	$ 325,807	$ 256,396	$ 382,465	$ 324,747	$ 241,362	$ 1,306,965	$ 1,204,970	$ 1,089,048
Segment operating income		$ (7,698)	66,804	38,473	12,064	(6,015)	54,328	$ 30,332	$ (9,183)	84,241	74,863	44,864
Interest income										319	1,165	658
Interest expense										(8,304)	(5,898)	(4,535)
Impairment recoveries (charges)			$ 24,467	$ 2,247	$ 2,384	$ (98)	$ (120)			29,098	(218)	(96)
Income from continuing operations before income taxes										104,350	64,729	37,935
Pursuit
Reportable segments reconciliations:
Impairment recoveries (charges)											(200)	(100)
Operating Segments
Reportable segments reconciliations:
Segment operating income										97,051	85,928	54,584
Operating Segments | GES
Reportable segments reconciliations:
Total revenue										1,133,097	1,054,739	976,878
Segment operating income										49,969	50,223	26,774
Operating Segments | Pursuit
Reportable segments reconciliations:
Total revenue										173,868	153,364	112,170
Segment operating income										47,082	35,705	27,810
Restructuring recoveries (charges)										(86)	(171)	(200)
Impairment recoveries (charges)										29,098	(218)	(96)
Intersegment Eliminations | GES
Reportable segments reconciliations:
Total revenue										(21,769)	(20,172)	(16,638)
Corporate Eliminations
Reportable segments reconciliations:
Total revenue	[1]										(3,133)
Segment operating income	[1]									67	(743)
Corporate
Reportable segments reconciliations:
Segment operating income										(12,877)	(10,322)	(9,720)
Restructuring recoveries (charges)										(211)	(560)	(402)
U.S.
Reportable segments reconciliations:
Total revenue										913,210	855,304	726,436
U.S. | Operating Segments | GES
Reportable segments reconciliations:
Total revenue										872,154	826,408	720,882
Segment operating income										34,494	40,524	14,563
Restructuring recoveries (charges)										354	(2,893)	(541)
International | Operating Segments | GES
Reportable segments reconciliations:
Total revenue										282,712	248,503	272,634
Segment operating income										15,475	9,699	12,211
Restructuring recoveries (charges)										$ (1,061)	$ (1,559)	$ (1,813)

[1] Corporate eliminations during 2017 represent the elimination of depreciation expense recorded by Pursuit associated with previously eliminated intercompany profit realized by GES for renovations to Pursuit’s Banff Gondola. Corporate eliminations recorded during 2016 represent the elimination of intercompany revenue and profit realized by GES for work completed on renovations to Pursuit’s Banff Gondola.