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Stock-based Compensation - Additional Information (Details) - shares | 1 Months Ended | 9 Months Ended
--- | --- | ---
May 31, 2016 | Feb. 29, 2016 | Sep. 30, 2016
Stock Options [Member] |  |  |
Additional disclosures [Abstract] |  |  |
Minimum age required for employees to qualify for immediate vesting of RSUs |  |  | 55 years
Threshold years required for retirement age |  |  | 70 years
Restricted Stock Units (RSUs) [Member] |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Vesting period |  | 1 year |
Additional disclosures [Abstract] |  |  |
Minimum age required for employees to qualify for immediate vesting of RSUs |  |  | 55 years
Threshold years required for retirement age |  |  | 70 years
Granted, shares |  | 114,517 | 126,067
Non Executive Employee |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Vesting period |  |  | 4 years
Directors [Member] |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Vesting period |  |  | 1 year
Directors [Member] | Restricted Stock Units (RSUs) [Member] |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Vesting period |  |  | 1 year
Employees [Member] | Restricted Stock Units (RSUs) [Member] |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Vesting period |  |  | 3 years
2010 Plan [Member] |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Increase in aggregate number of shares authorized for issuance | 170,000 |  |
Shares authorized for issuance | 1,108,560 |  |
2015 ESPP [Member] |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Percentage related to employees to purchase shares at the lower fair market value at offering period |  |  | 85.00%

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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. + 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)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + 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). + 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 (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + 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 Number of additional shares authorized for issuance under an established share-based compensation plan. + References No definition available. + Details
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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 + Details
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- Definition Minimum age required for employees to qualify for immediate vesting of RSUs. + References No definition available. + Details
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- Definition Threshold years required for retirement age (defined as employees that are a minimum of 55 years of age and the sum of their age plus years of full-time employment with the Company). + References No definition available. + Details
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