Discontinued operations - Classes of Assets and Liabilities of Discontinued Components (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash	$ 4,592
Accounts receivable	15,822
Prepayments and other receivables	9,476
Amount due from related party	2,079
Property, plant and equipment	633
Long-term deferred expenses	31
Deferred tax assets	866
Goodwill	16,926
Assets of discontinued components	50,425
Accounts payable	14,167
Accrued expenses and other payables	15,764
Amount due to related party	205
Income tax payable	9,524
Acquisition payable	22,196
Liabilities of discontinued components	$ 61,856

Disposal Group Including Discontinued Operation Amount Acquisition Payable

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- Definition

Disposal Group Including Discontinued Operation Amount Due From Related Party

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Disposal Group Including Discontinued Operation Amount Due To Related Party

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- Definition

Disposal Group Including Discontinued Operation Long Term Deferred Expenses

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- Definition

The aggregate value (measured at the lower of net carrying value or fair value less cost of disposal) for assets of a disposal group, including a component of the entity (discontinued operation), to be sold or that has been disposed of through sale, as of the financial statement date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 45

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-Paragraph 46

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

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For the disposal group, including a component of the entity (discontinued operation), the aggregate of amounts due from customers or clients for goods or services that have been delivered or sold in the normal course of business and an amount representing an agreement for an unconditional promise by the maker to pay the entity (holder) a definite sum of money at a future date, reduced to their estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection and net of any write-downs taken for collection uncertainty on the part of the holder, respectively.

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For the disposal group, including a component of the entity (discontinued operation), carrying value of obligations incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business.

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- Definition

For the disposal group, including a component of the entity (discontinued operation), carrying amount as of the unpaid sum of the known and estimated amounts payable to satisfy domestic and foreign income tax obligations. In theory, the sum represents amounts due to tax jurisdictions based on tax returns as if they were ready and available for filing on and as of the balance sheet date.

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- Definition

For the disposal group, including a component of the entity (discontinued operation), carrying value of obligations incurred and payable pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include interest, rent, salaries, and utilities.

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For the disposal group, including a component of the entity (discontinued operation), cash includes currency on hand as well as demand deposits with banks or financial institutions. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 144

-Paragraph 47

-Subparagraph a

-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.

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-Publisher FASB

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-Paragraph 7, 8, 9

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-Glossary Cash

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- Definition

For a disposal group, including a component of the entity (discontinued operation), represents the deferred tax assets (net of any valuation allowances), which result from applying the applicable tax rate to net deductible temporary differences and carryforwards pertaining to each jurisdiction to which the entity is obligated to pay income tax. A deductible temporary difference is a difference between the tax basis and the carrying amount of an asset or liability in the financial statements prepared in accordance with generally accepted accounting principles that will result in deductible amounts for tax purposes in future periods if there is sufficient tax-basis income to enable the deduction to be taken.

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- Definition

For the disposal group, including a component of the entity (discontinued operation), carrying amount of goodwill (adjusted for any amortization recognized prior to adoption of FAS 142 and impairment charges).

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For the disposal group, including a component of the entity (discontinued operation), carrying amount of assets not otherwise specified in the taxonomy that are expected to be realized or consumed within one year or the normal operating cycle, if longer.

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For the disposal group, including a component of the entity (discontinued operation), carrying value (net of accumulated depreciation and any write-downs) of tangible assets that are held by an entity for use in the production or supply of goods and services, for rental to others, or for administrative purposes and that are expected to provide economic benefit for more than one year. Examples include land, buildings, machinery and equipment, and other types of furniture and equipment including, but not limited to, office equipment, furniture and fixtures, and computer equipment and software.

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- Definition

The obligations arising from the sale, disposal, or planned sale in the near future (generally within one year) of a disposal group, including a component of the entity (discontinued operation).

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