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Performance period of restricted stock and restricted stock units

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Unrecognized cost of unvested options awarded to employees as compensation.

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Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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 non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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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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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Number of non-vested options outstanding.

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Number of non-vested options forfeited.

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Number of shares (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP), net of any shares forfeited. Shares issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.

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Share-Based Compensation (Narrative) (Details) $ in Millions	1 Months Ended		6 Months Ended
	Feb. 28, 2018 executive	Mar. 31, 2017 USD ($) shares	Jun. 30, 2018 USD ($) shares	Feb. 28, 2015 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period of restricted stock units (in years)		3 years	3 years
Number of executives awarded stock options \| executive	4
Unrecognized compensation expense \| $			$ 0.6
Period for recognition for unrecognized compensation expense			3 years 7 months 24 days
Incentive Award Plan 2015 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized (in shares)				4,900,000
RSUs awarded (in shares)			0
Incentive Award Plan 2015 [Member] \| Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant (in shares)			4,742,750
Target Restricted Stock Units, 2016 Grants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested options forfeited (in shares)			18,500
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Option vesting term (in years)			10 years
Employee Stock Option [Member] \| Incentive Award Plan 2015 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of nonvested options (in shares)			80,000
Requisite service period	4 years
Restricted Stock [Member] \| Incentive Award Plan 2015 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of nonvested shares (in shares)			77,250
Restricted Stock [Member] \| Target Restricted Stock Units, 2014 Grants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares vested in period, amount \| $		$ 3.6
RSUs vested during period (in shares)		61,445