Equity-Based Compensation, Profit Sharing and Deferred Compensation Plans - Summary of Equity-Based Compensation Plans with Grants Outstanding (Detail)	Dec. 31, 2017 shares
1998 Management Long-Term Stock Option Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares Authorized	1,000,000
Options/RSUs Outstanding	6,000
Shares Available to Issue	0
2000 Broadly-Based Stock Option Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares Authorized	2,000,000
Options/RSUs Outstanding	89,000
Shares Available to Issue	0
2010 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares Authorized	700,000
Options/RSUs Outstanding	218,000
Shares Available to Issue	38,000
2014 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares Authorized	950,000
Options/RSUs Outstanding	613,000
Shares Available to Issue	276,000

Share based compensation arrangement by share based payment award options and restricted share units outstanding number.

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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.

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ 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)(3)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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