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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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Amount of tax benefit from exercise of option under share-based payment arrangement.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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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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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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Number of shares authorized for issuance under share-based payment arrangement.

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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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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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Incentive Plans (Narrative) (Details)		1 Months Ended	6 Months Ended
Incentive Plans (Narrative) (Details)	Aug. 30, 2013 USD ($) shares	Feb. 29, 2020 $ / shares company	Jun. 30, 2020 USD ($) $ / shares	Jun. 30, 2019 USD ($)	Aug. 08, 2013 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation \| $			$ 5,600,000	$ 5,400,000
Total income tax benefits realized from tax deductions related to stock option exercises under share-based payment arrangements \| $			$ 0	$ 100,000
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)			$ 123.65
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) \| shares	5,500,000
Number of shares per employee (no more than) (in shares) \| shares	1,000,000
Award expiration period		7 years
2013 Long-Term Incentive Plan \| Performance Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum amount payable \| $	$ 5,000,000.0
2013 Long-Term Incentive Plan \| Nonqualified Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted, fair value (in dollars per share)		$ 28.28
2013 Long-Term Incentive Plan \| Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)			3 years
2013 Long-Term Incentive Plan \| Return On Average Capital Employed Performance Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)		3 years
Restricted stock units issued, weighted average grant date fair value (in dollars per share)		$ 106.72
2013 Long-Term Incentive Plan \| Total Shareholder Return Performance Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)		3 years
Number of companies in total shareholder return peer comparison group \| company		18
Restricted stock units issued, weighted average grant date fair value (in dollars per share)		$ 142.07
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) \| shares					500,000
2013 Stock Plan For Non-Employee Directors \| Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)			3 years
Restricted stock units issued, weighted average grant date fair value (in dollars per share)			$ 105.33