Segment Information - Reconciliation of Income Statement Items from Reportable Segments (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Reportable segments reconciliations:
Total revenue		$ 363,677	$ 364,774	$ 641,105	$ 690,581
Segment operating income		36,244	37,703	23,228	48,282
Interest income		53	42	137	100
Interest expense		(2,354)	(2,059)	(4,423)	(4,164)
Other expense	[1]	(543)	(222)	(781)	(674)
Restructuring recoveries (charges)		(662)	(168)	(824)	(562)
Impairment recoveries				35	4,631
Income from continuing operations before income taxes		32,773	37,543	17,372	47,613
GES
Reportable segments reconciliations:
Total revenue		315,322		583,028
Pursuit
Reportable segments reconciliations:
Total revenue		48,355		58,077
Operating Segments
Reportable segments reconciliations:
Segment operating income		38,762	40,607	27,947	53,711
Operating Segments | GES
Reportable segments reconciliations:
Total revenue		315,322	320,109	583,028	637,980
Segment operating income		29,005	30,669	29,585	54,048
Operating Segments | Pursuit
Reportable segments reconciliations:
Total revenue		48,355	44,665	58,077	52,601
Segment operating income		9,757	9,938	(1,638)	(337)
Restructuring recoveries (charges)				(140)
Impairment recoveries		35	2,247	35	4,631
Intersegment Eliminations | GES
Reportable segments reconciliations:
Total revenue		(6,346)	(7,205)	(9,694)	(10,444)
Intersegment Eliminations | Pursuit
Reportable segments reconciliations:
Total revenue		(500)		(706)
Corporate Eliminations
Reportable segments reconciliations:
Segment operating income	[2]	17	16	33	32
Corporate
Reportable segments reconciliations:
Segment operating income		(2,535)	(2,920)	(4,752)	(5,461)
Restructuring recoveries (charges)				10	(137)
Domestic Plans | Operating Segments | GES
Reportable segments reconciliations:
Total revenue		241,239	242,031	445,107	499,242
Segment operating income		20,838	21,320	19,282	42,666
Restructuring recoveries (charges)		(240)	(47)	(240)	(71)
International | Operating Segments | GES
Reportable segments reconciliations:
Total revenue		80,429	85,283	147,615	149,182
Segment operating income		8,167	9,349	10,303	11,382
Restructuring recoveries (charges)		$ (422)	$ (121)	$ (454)	$ (354)

[1] We adopted ASU 2017-07 on January 1, 2018, which requires retrospective adoption. As a result, we recorded the nonservice cost component of net periodic benefit cost within other expense for the three and six months ended June 30, 2018, and we reclassified $0.2 million from operating expenses to other expense for the three months ended June 30, 2017 and $0.7 million for the six months ended June 30, 2017 to conform with current period presentation. Refer to Note 1 – Overview and Basis of Presentation for additional details on the impact of this adoption on our Condensed Consolidated Statements of Operations.

[2] Corporate eliminations 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.