Share-based Payment Arrangements - Additional Information (Detail) $ in Thousands	3 Months Ended
Mar. 31, 2018 USD ($) EquityPlan shares	Apr. 01, 2017 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of employee equity incentive plans \| EquityPlan	2
Income tax benefit realized on disqualifying dispositions of stock acquired by exercise of incentive stock options	$ 50	$ 221
Accounting Standards Update 2016-09
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Excess tax benefit from stock-based awards	$ 1,298	563
2013 Directors Stock Compensation Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock authorized for issuance \| shares	115,000
Common stock reserved for issuance \| shares	78,682
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Recognized share-based compensation expense	$ 3,153	524
Unrecognized compensation cost expected to be recognized over period, years	3 years 6 months
Non Vested Restricted Stock and Deferred Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost, other than options	$ 4,236
Unrecognized compensation cost expected to be recognized over period, years	2 years 10 months 25 days
Terms of award	The Company’s common stock on the date of grant. Shares of non-vested restricted stock are generally subject to vesting in three equal annual installments either on the first, second and third anniversary of the date of the grant or the third, fourth and fifth anniversary of the date of the grant, or 100% on the first anniversary of the date of the grant. For restricted stock awards granted under the 2013 DSCP plan, each recipient may elect to defer receipt of shares and instead receive restricted stock units (“Deferred Stock Units”), which represent contingent rights to receive shares of the Company’s common stock on the date of recipient separation from service from the Board of Directors, or, if earlier, upon a change in control event of the Company. Deferred Stock Units become vested 100% on the first anniversary of the date of the grant.
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total intrinsic value of stock options exercised during periods	$ 2,463	$ 3,620
Unrecognized compensation cost, stock options	0
Maximum \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost, other than options	$ 30,200
2011 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock authorized for issuance \| shares	6,000,000
2013 Directors Stock Compensation Plan \| Deferred Stock Unit
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock vesting percentage	100.00%
Other Stock Compensation Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance \| shares	4,519,920

Number of employee equity incentive plans.

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Aggregate number of common shares reserved for future issuance.

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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.

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

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Unrecognized cost of unvested options awarded to employees as compensation.

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Amount of tax benefit from exercise of stock options granted under share-based compensation arrangement.

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Amount of the effect of a change in accounting principle on net income.

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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.

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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).

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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Description of pertinent provisions of equity-based compensation awards that have actual or potential impact upon the company's financial statements.

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Percentage of vesting of share-based compensation awards.

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