Income Taxes (Effective Income Tax Rate Reconciliation) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Reconciliation between income tax expense computed by applying PRC tax rate and actual:
Income before income tax expense	$ 62,695	$ 25,855	$ 9,011
PRC statutory income tax rate (in percentage)	25.00%	25.00%	25.00%
Income tax expense at statutory income tax rate	15,674	6,464	2,253
Permanent differences	870	116	75
Effect of different income tax calculation method required by tax bureau	67	(84)	(2,416)
Effect of different income tax rates in other jurisdictions	12,192	10,585	1,093
Effect of income tax holiday and preferential tax rates	(17,844)	(7,036)	(717)
Changes in valuation allowance	420	829	175
Total income tax expense	$ 11,379	$ 10,874	$ 463
Positive impact of tax holidays on basic net income per ordinary share	$ 0.10	$ 0.05	$ 0.01

Income Tax Reconciliation, Different income tax calculation method

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Basic earnings per ordinary shares effect of domestic income tax expense benefit difference due to tax exemptions and reductions.

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The domestic federal statutory tax rate applicable under enacted tax laws to the Company's pretax income from continuing operations for the period. The "statutory" tax rate is the regular tax rate if there are alternative tax systems.

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Sum of operating profit and nonoperating income or expense before Income or Loss from equity method investments, income taxes, extraordinary items, and noncontrolling interest.

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The sum of the current income tax expense or benefit and the deferred income tax expense or benefit pertaining to continuing operations.

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The portion of the difference, between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations, that is attributable to total foreign income tax expense or benefit. The foreign income tax expense or benefit difference represents the income tax expense or benefit at applicable domestic statutory income tax rates applied to foreign earnings or loss for the period versus the foreign income tax expense or benefit calculated by applying the appropriate foreign tax rates.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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The portion of the difference between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to nondeductible expenses under enacted tax laws, or differences in the methodologies used to determine expense amounts for financial statements prepared in accordance with generally accepted accounting principles, not otherwise listed in the existing taxonomy.

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The portion of the difference between total income tax expense or benefit as reported in the Income Statement and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to income that is exempt from income tax because of [foreign] tax holidays an entity has received in the period. A foreign tax "holiday" refers to a foreign jurisdiction that attempts to attract in-coming or foreign investment by offering an exemption from income taxes for some defined period of time.

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