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Stock Option Plans - Narrative (Details) | 9 Months Ended |
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Sep. 30, 2017 USD ($) compensation_plan shares | Sep. 29, 2017 $ / shares
Disclosure of Compensation Related Costs, Share-based Payments [Abstract] |  |
Number of stock option plans | compensation_plan | 2 |
Option expiration period | 10 years |
Option vesting period | 4 years |
Closing share price (in usd per share) | $ / shares |  | $ 61.91
Granted (in shares) | shares | 232,500 |
Intrinsic value of granted shares | $ | $ 581,250 |
Weighted average remaining contractual life of the Company's outstanding options | 7 years 7 months 29 days |
Weighted average remaining contractual life of the Company's exercisable options | 6 years 8 months |

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- Definition Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Intrinsic Value + References No definition available. + Details
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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=96867065&loc=d3e5070-113901 + Details
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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. + 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)(2) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, 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 -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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