Goodwill and Other Intangible Assets - Goodwill by Reporting Unit and Segment (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Goodwill [Line Items]
Goodwill	$ 130,999	$ 137,820
Marketing & Events U.S. [Member]
Goodwill [Line Items]
Goodwill	62,686	62,686
Marketing & Events Group [Member]
Goodwill [Line Items]
Goodwill	85,276	85,740
Marketing & Events Group [Member] | Marketing & Events U.S. [Member]
Goodwill [Line Items]
Goodwill	62,686	62,686
Marketing & Events International [Member] | GES United Kingdom [Member]
Goodwill [Line Items]
Goodwill	13,766	13,894
Marketing & Events International [Member] | GES Canada [Member]
Goodwill [Line Items]
Goodwill	8,824	9,160
Travel & Recreation Group [Member]
Goodwill [Line Items]
Goodwill	45,723	52,080
Travel & Recreation Group [Member] | Brewster [Member]
Goodwill [Line Items]
Goodwill	42,539	44,435
Travel & Recreation Group [Member] | Alaska Denali Travel [Member]
Goodwill [Line Items]
Goodwill	3,184	3,184
Travel & Recreation Group [Member] | Glacier Park [Member]
Goodwill [Line Items]
Goodwill		$ 4,461