Related Party Transactions - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2012
Related Party Transaction [Line Items]
Total consideration received for sale of fully furnished residential flats, along with car parking spaces	$ 1.1
Transaction with CEO and President of the Company
Related Party Transaction [Line Items]
Gain from sale of fully furnished residential flats, along with car parking spaces	$ 0.9

Reflects the sum of all other revenue and income realized from sales and other transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party during the period.

No definition available.

Name:	us-gaap_RelatedPartyTransactionOtherRevenuesFromTransactionsWithRelatedParty
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration