Number Of Companies In Total Shareholder Return Peer Comparison Group

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Share Base Compensation Arrangement By Share Based Payment Awards, Maximum Amount Payable

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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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The per share price that the individual must pay to acquire shares under the deferred compensation arrangement.

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

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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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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).

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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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For each plan, identification of the award pricing model or other valuation method used in calculating the weighted average fair values disclosed. The model is also used to calculate the compensation expense that is shown within the balance sheet, income statement, and cash flow. Examples of valuation techniques are lattice models (binomial model), closed-form models (Black-Scholes-Merton formula), and a Monte Carlo simulation technique. Fair value is the amount at which an asset or liability could be bought or incurred or sold or settled in a current transaction between willing parties, that is, other than in a forced or liquidation sale. May include disclosures about the assumptions underlying application of the method selected.

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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 highest quantity of shares an employee can purchase under the plan per period.

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

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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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Incentive Plans (Details)				3 Months Ended	9 Months Ended
Incentive Plans (Details)	Mar. 27, 2018 $ / shares shares	Feb. 07, 2018 $ / shares company shares	Aug. 30, 2013 USD ($) shares	Mar. 31, 2018 $ / shares shares	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)	Aug. 08, 2013 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation \| $					$ 6,800,000	$ 4,700,000
Total income tax benefits realized from tax deductions related to stock option exercises under share-based payment arrangements \| $					$ 2,100,000	$ 200,000
2013 Long-Term Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for incentive plan (no more than) (in shares)			5,500,000
Number of shares per employee (no more than) (in shares)			1,000,000
2013 Long-Term Incentive Plan \| Performance Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum amount payable \| $			$ 5,000,000
Restricted stock units issued (in shares)		44,700
2013 Long-Term Incentive Plan \| Nonqualified Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted (in shares)		93,600
Shares granted, exercise price (in dollars per share) \| $ / shares		$ 71
Shares granted, fair value determination method					Black-Scholes
Shares granted, fair value (in dollars per share) \| $ / shares		17.32
2013 Long-Term Incentive Plan \| Return On Average Capital Employed Performance Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units issued, weighted average grant date fair value (in dollars per share) \| $ / shares		$ 71.00
Award vesting period (in years)		3 years
2013 Long-Term Incentive Plan \| Total Shareholder Return Performance Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted, fair value determination method					Monte Carlo
Restricted stock units issued, weighted average grant date fair value (in dollars per share) \| $ / shares		$ 87.60
Award vesting period (in years)		3 years
Number of companies in total shareholder return peer comparison group \| company		16
2013 Long-Term Incentive Plan, RSU Grant One \| Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units issued (in shares)		22,350
Restricted stock units issued, weighted average grant date fair value (in dollars per share) \| $ / shares		$ 71.00
2013 Long-Term Incentive Plan, RSU Grant Two \| Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units issued (in shares)	43,905
Restricted stock units issued, weighted average grant date fair value (in dollars per share) \| $ / shares	$ 72.88
2013 Stock Plan For Non-Employee Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for incentive plan (no more than) (in shares)							500,000
2013 Stock Plan For Non-Employee Directors \| Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units issued (in shares)				10,800
Restricted stock units issued, weighted average grant date fair value (in dollars per share) \| $ / shares				$ 69.42
Award vesting period (in years)				3 years