Common stock issue price per share.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Unrecognized cost of unvested share-based compensation awards.

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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.

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- Definition

The cash inflow from the additional capital contribution to the entity.

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- Definition

The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued 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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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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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.

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No definition available.

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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.

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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.

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- Definition

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

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- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

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- Definition

Percentage of vesting of share-based compensation awards.

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- Definition

Intrinsic value of equity-based compensation awards vested. Excludes stock and unit options.

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No definition available.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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- Definition

Number of share options (or share units) exercised during the current period.

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Equity and Stock-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended		9 Months Ended		12 Months Ended
	Jul. 03, 2017	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2012	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, shares issued	2,807,017	43,559,081		43,559,081			33,844,074
Common stock issue price per share	$ 42.75
Exercised number of shares				201,966
Net proceeds from public offering	$ 129,300			$ 129,309
Stock-based compensation expense		$ 1,817	$ 1,282	$ 4,845	$ 3,341
Stock options, outstanding		749,669		749,669			882,748
Number of shares available for future grant		1,228,987		1,228,987
Closing price of common stock		$ 38.32		$ 38.32
Weighted average grant date fair value of share-based awards granted				$ 16.94	$ 13.55
Total fair value of stock options vested				$ 2,074	$ 1,590
Total unrecognized compensation cost		$ 18,114		$ 18,114
Unrecognized compensation cost, weighted average remaining requisite service period				2 years 8 months
Employee Stock Option \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Incentive options, vesting period						3 years
Employee Stock Option \| Minimum \| Vest Over Three Year
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Incentive options, vesting percentage						20.00%
Employee Stock Option \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Incentive options, vesting period						5 years
Incentive options, term						10 years
Employee Stock Option \| Maximum \| Vest Over Five Year
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Incentive options, vesting percentage						33.00%
Non-Employee Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Incentive options, vesting period						1 year
Option To Purchase Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, outstanding		749,669	1,198,673	749,669	1,198,673
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units, outstanding		515,468		515,468
Closing price of common stock		$ 38.32		$ 38.32
Aggregate intrinsic value of restricted stock units vested				$ 3,480	$ 1,479
Weighted average grant date fair value of restricted stock units granted				$ 36.85	$ 26.28
Total grant date fair value of restricted stock units vested				$ 2,565	$ 1,315
Underwriters \| Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercised number of shares	421,052