Income Tax Expense - Reconciliation of Beginning and Ending Amount of Unrecognized Tax Benefits (Detail) $ in Thousands	6 Months Ended
Jun. 30, 2015 USD ($)
Income Tax Disclosure [Abstract]
Unrecognized tax benefits at the beginning of year	$ 23
Additions for tax positions of current year	50
Additions for tax positions of prior years	0
Reductions for settlements with taxing authorities	0
Reductions for lapses of the applicable statutes of limitations	0
Unrecognized tax benefits at the end of the period	$ 73

No definition available.

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- Definition

Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15A

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

-URI http://asc.fasb.org/extlink&oid=6527854

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- Definition

Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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