For each tranche, the maximum percentage of earnings based upon the Company's total shareholder return.

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For each tranche, the minimum percentage of earnings based upon the Company's total shareholder return.

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The performance period (in years) of each PSUs.

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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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Disclosure of the aggregate tax benefit realized from the exercise of stock options and the conversion of similar instruments during the annual period.

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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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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 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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Net 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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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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Stockholders' Equity and Equity Instruments - Plan Information (Details) $ / shares in Units, $ in Millions	3 Months Ended	9 Months Ended
	Mar. 31, 2015 shares	Sep. 30, 2015 USD ($) award_type $ / shares shares	Sep. 30, 2014 USD ($)	May. 31, 2015 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reissued shares of treasury stock (in shares)		31,141
Tax benefit from equity compensation awards recorded as additional paid-in capital \| $		$ 0.1
Compensation expense recorded during period pursuant to stock-based compensation plans \| $		$ 4.9	$ 3.7
2015 Incentive Award Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized for issuance (in shares)				3,000,000
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted (in shares)		120,956
Vesting period		4 years
Options expiration period		7 years
Fair value measurement method		Black-Scholes option valuation model
Weighted-average grant date fair value of options (in dollars per share) \| $ / shares		$ 14.78
Reissued shares of treasury stock (in shares)		31,104
RSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)		19,492
Vesting period		3 years
Reissued shares of treasury stock (in shares)		15,952
PSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)		35,584
Vesting period		3 years
Performance period of PSUs		3 years
Minimum percentage of earnings (in hundredths)		0.00%
Maximum percentage of earnings (in hundredths)		150.00%
Number of award types \| award_type		2
PSUs [Member] \| 2012 Grant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reissued shares of treasury stock (in shares)	10,454	10,454
TSR PSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period of PSUs		3 years
Fair value measurement method		Monte-Carlo simulation model
ROIC PSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period of PSUs		3 years