Summary of Adjustments to Uncertain Tax Position (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Income Tax Contingency [Line Items]
Beginning Balance	$ 275	$ 275	$ 238
Increase/Decrease for tax positions related to the current year
Increase/Decrease for tax positions related to prior years			37
Decreases for settlements with applicable taxing authorities
Decreases for lapses of statute of limitations
Ending Balance	$ 275	$ 275	$ 275

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The gross amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns as of the balance sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

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The gross amount of increases in unrecognized tax benefits resulting from tax positions that have been or will be taken in the tax return for the current period, excluding amounts pertaining to examined tax returns.

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The gross amount of increases in unrecognized tax benefits resulting from tax positions taken in prior period tax returns, excluding amounts pertaining to examined tax returns.

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

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The gross amount of increases in unrecognized tax benefits resulting from settlements with taxing authorities.

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The gross amount of decreases in unrecognized tax benefits resulting from lapses of the applicable statutes of limitations.

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