Goodwill and Intangible Assets - Schedule of Changes in Goodwill and Intangible Assets with Indefinite Lives (Detail) (USD $) In Thousands, unless otherwise specified	6 Months Ended
Jun. 30, 2013
Goodwill And Intangible Assets Disclosure [Abstract]
Balance at beginning of period	$ 31,785
Goodwill from Xtrakter acquisition	26,234
Intangible assets with indefinite lives from Xtrakter acquisition	2,120
Balance at end of period	$ 60,139

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=14024403&loc=d3e13816-109267

Name:	us-gaap_GoodwillAcquiredDuringPeriod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration