Stock-Based Compensation (Details)	6 Months Ended
Jun. 30, 2018 plan $ / shares shares	Sep. 28, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Number of plans \| plan	3
Stock dividend, percent		3.00%
Roll-Forward of Shares Outstanding - Weighted Average Exercise Price:
Fair Value, in dollars per share	$ 5.76
Dividend Yield	2.98%
Expected Volatility	21.55%
Risk Free Interest Rate	2.68%
Expected Lives, in years	6 years 11 months 23 days
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award expiration period (in years)	10 years
Award vesting period (in years)	4 years
Roll-Forward of Shares Outstanding:
Outstanding, Beginning of Period, in shares \| shares	346,155
Granted, in shares \| shares	55,188
Exercised, in shares \| shares	(79,001)
Forfeited, in shares \| shares	(6,321)
Outstanding, End of Period, in shares \| shares	316,021
Exercisable at Period End, in shares \| shares	198,544
Vested and Expected to Vest, in shares \| shares	117,477
Roll-Forward of Shares Outstanding - Weighted Average Exercise Price:
Outstanding at Beginning of Period, in dollars per share	$ 24.12
Granted, in dollars per share	30.85
Exercised, in dollars per share	21.41
Forfeited, in dollars per share	29.94
Outstanding, End of Period, in dollars per share	25.85
Exercisable at Period End, in dollars per share	23.06
Vested and Expected to Vest, in dollars per share	$ 30.55
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)	3 years

Share-based Compensation Arrangement, Number of Plans

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Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Including Stock Dividends

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Stock Dividend, Percent

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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 estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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- Definition

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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The risk-free interest rate assumption that is used in valuing an option on its own shares.

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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 number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Gross number of share options (or share units) granted during the period.

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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.

+ 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

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Number of fully vested and expected to vest exercisable options that may be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for fully vested and expected to vest exercisable or convertible options. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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- Definition

Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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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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Expected term of share-based compensation awards, 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
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-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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