Stock Based Compensation - Summary of Changes in Nonvested RSUs (Details) (RSUs, USD $)	9 Months Ended
Sep. 30, 2014	Sep. 30, 2013
RSUs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Nonvested RSUs, Beginning balance	26,120	0
Nonvested RSUs, Granted	32,275	26,120
Nonvested RSUs, Vested	(58,395)	0
Nonvested RSUs, Forfeited	0	0
Nonvested RSUs, Ending balance	0	26,120
Weighted-Average Granted-Date Fair Value, Nonvested RSUs Beginning balance	$ 10.77	$ 0
Weighted-Average Granted-Date Fair Value, Nonvested RSUs, Granted	$ 14.08	$ 10.77
Weighted-Average Granted-Date Fair Value, Nonvested RSUs, Vested	$ 12.60	$ 0
Weighted-Average Granted-Date Fair Value, Nonvested RSUs, Forfeited	$ 0	$ 0
Weighted-Average Granted-Date Fair Value, Nonvested RSUs, Ending balance	$ 0	$ 10.77

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Gross number of share options (or share units) granted during the period.

+ References

No definition available.

+ Details

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (d)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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- Definition

Number of non-vested options outstanding.

+ References

No definition available.

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- Definition

Number of non-vested options forfeited.

+ References

No definition available.

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- Definition

Weighted average grant-date fair value of non-vested options forfeited.

+ References

No definition available.

+ Details

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- Definition

Weighted average grant-date fair value of non-vested options outstanding.

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No definition available.

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- Definition

Number of options vested.

+ References

No definition available.

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- Definition

Weighted average grant-date fair value of options vested.

+ References

No definition available.

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