Earnings Per Share - Additional Information (Detail) - $ / shares	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Earnings Per Share [Line Items]
Participating securities outstanding	0	0
Stock options, outstanding	805,903		882,748
Stock options, weighted average exercise price	$ 19.68		$ 16.88
Common stock excluded from calculation of diluted earnings per share	458,685	520,030
Option To Purchase Common Stock
Earnings Per Share [Line Items]
Stock options, outstanding	805,903	1,312,508
Stock options, weighted average exercise price	$ 19.68	$ 11.50
Restricted Stock Units (RSUs)
Earnings Per Share [Line Items]
Common stock excluded from calculation of diluted earnings per share	404,781

Earnings Per Share [Line Items]

No definition available.

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- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Antidilution
-URI http://asc.fasb.org/extlink&oid=6505113

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6510752

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- Definition

This element represents nonvested share-based payment awards that contain non-forfeitable rights to dividends or dividend equivalents (whether paid or unpaid). Basic and dilutive earnings per share are generally disclosed for such shares using the two-class method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
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- Definition

Number of options outstanding, including both vested and non-vested options.

+ References

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

+ References

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