Overview and Summary of Significant Accounting Policies - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013 CompensationPlan Segment	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Number of reportable segments	2
Percentage of total consolidated revenues representing fulfillment services contracts	1.30%	1.50%	1.40%
Cash and cash equivalents	$ 211,985	$ 187,322	$ 211,122	$ 189,829
Interest bearing investments, original maturities	Less than 90 days	Less than 90 days
Tax position measurement	Greater than 50%
Period over which up-front fees, included within deferred revenue, are earned	12 months
Number of stock-based compensation plan	3
Minimum [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Deferred revenue recognition period	30 days
Non-deliverable forward contracts and options expiring period	1 month
Maximum [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Deferred revenue recognition period	7 years
Non-deliverable forward contracts and options expiring period	24 months
Equipment [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Useful life of equipment	5 years
International Operations [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Cash and cash equivalents	$ 195,000	$ 182,900
Alpine Access, Inc [Member] | Americas [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Business acquisition date	Aug. 20, 2012