Subsequent Event - Acquisition - Additional Information (Detail) (USD $) In Millions, unless otherwise specified		1 Months Ended
Jul. 31, 2012 Country	Sep. 30, 2012 Global Novations, LLC Subsequent Event Item Country	Sep. 01, 2012 Global Novations, LLC Subsequent Event Country
Subsequent Event [Line Items]
Number of offerings		150
Number of countries in which it operates	35		40
Business acquired, cash paid			$ 35
Business acquired, additional consideration that dependent on future performance			$ 5
Years of experience and service period		30 years

Amount of cash paid to acquire the entity.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141R

-Paragraph 68

-Subparagraph f(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 51

-Subparagraph d

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Name:	us-gaap_BusinessAcquisitionCostOfAcquiredEntityCashPaid
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant