Stock-Based Compensation - Restricted Stock - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected weighted average period	1 year 4 months 24 days
Rate of forfeiture of shares	3.00%	3.00%	3.00%
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of restricted shares received	950,340	825,120	609,355
Unrecognized compensation expense related to restricted stock awards	$ 2.9
Expected weighted average period	1 year 7 months 6 days
Restricted Stock [Member] \| Non Employee Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of restricted shares received	10,000
Restricted stock, vesting percentage	25.00%
Restricted stock, vesting period	Three quarters

Restricted Stock Award Forfeitures Rate

No definition available.

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

+ Details

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- Definition

Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

+ References

No definition available.

+ Details

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- Definition

General descriptive information regarding an arrangement under which employees and directors receive: (a) awards of equity shares, equity share options, or other equity instruments; or (b) the entity incurs liabilities to them: (1) in amounts based, at least in part, on the price of the entity's shares or other equity instruments; or (2) that require or may require settlement by issuance of the entity's shares. Such an arrangement is usually provided to employees and directors to compensate them, provide performance incentives to them, and to attract or retain their services. May also include pertinent information particular to a plan that is not elsewhere specified in the taxonomy.

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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901

+ Details

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Percentage of vesting of share-based compensation awards.

+ References

+ Details

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- Details

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