Grant date fair value of share-based awards other than options.

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term for Expected Dividend Rate

+ References

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term for Expected Volatility Rate

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No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term for Risk Free Interest Rate

+ References

No definition available.

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- Definition

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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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

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- Definition

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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- Definition

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.

+ References

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- Definition

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.

+ References

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- Definition

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).

+ References

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- Definition

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.

+ References

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- Definition

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.

+ References

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- Definition

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.

+ References

No definition available.

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- Definition

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).

+ References

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- Definition

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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- Definition

Percentage of vesting of share-based compensation awards.

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- Definition

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.

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- Definition

Number of new stock issued during the period.

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Stock Based Compensation - Narrative (Details) - USD ($) $ in Millions	1 Months Ended		3 Months Ended		6 Months Ended
	May 31, 2017	May 31, 2015	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017	Dec. 31, 2016
Performance Share Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period		3 years
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Non-vested shares (in shares)			424,341	501,770	424,341	501,770	422,928	319,058
Shares granted (in shares)					206,597	332,921
2010 Stock Incentive Plan \| Performance Share Awards \| Board of Directors Chairman
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted (in shares)		89,629
Fair value of shares granted		$ 0.4
Fair value, expected term		3 years
Fair value, expected term for volatility rate		3 years
Fair value, expected term for risk free interest rate		3 years
Fair value, expected term for dividend rate		3 years
Award vesting period	3 years	3 years
2010 Stock Incentive Plan \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Non-vested shares (in shares)			217,163		217,163
Share-based compensation expense			$ 0.3	$ 0.4	$ 0.6	$ 0.7
Unrecognized compensation cost			$ 2.1	$ 2.7	$ 2.1	2.7
Unrecognized compensation cost, period for recognition					2 years 20 days
Fair value of vested shares					$ 1.1	$ 1.0
Requisite service period					3 years
2017 Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of shares that may be issued (in shares)			5,570,000		5,570,000
Shares available for grant (in shares)			4,237,065		4,237,065
2017 Incentive Plan \| Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued (in shares)					131,975
2017 Incentive Plan \| Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued (in shares)					209,264
2017 Incentive Plan \| Performance Share Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of shares that may be issued (in shares)	653,365
Shares available for grant (in shares)			991,696		991,696
Share-based compensation expense			$ 0.2		$ 0.2
Unrecognized compensation cost			$ 2.4		$ 2.4
Fair value of shares granted	$ 2.7
Award vesting period	3 years
2017 Incentive Plan \| Performance Share Awards \| Relative TSR performance Is Less Than The Thirtieth Percentile
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights, percentage	0.00%
2017 Incentive Plan \| Performance Share Awards \| Relative TSR Performance Is Equal To The Fiftieth Percentile
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights, percentage	100.00%
2017 Incentive Plan \| Performance Share Awards \| Board of Directors Chairman
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value, expected term	3 years
Fair value, expected term for volatility rate	3 years
2017 Incentive Plan \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Non-vested shares (in shares)			207,178		207,178