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Share-Based Compensation (Narrative) (Details) - USD ($) $ in Millions	1 Months Ended		3 Months Ended
	Mar. 31, 2017	Feb. 29, 2016	Mar. 31, 2017	Feb. 28, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period of restricted stock units (in years)			3 years
Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued during period		88,074
Shares withheld for payroll taxes			58,822
Incentive Award Plan 2015 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized				4,900,000
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	4,711,000		4,711,000
Shares issued during period			0
Target Restricted Stock Units, 2016 Grants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested options forfeited			2,500
Target Restricted Stock Units, 2015 Grants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested options forfeited			3,500
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Option vesting term (in years)			10 years
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
RSUs vested during period		146,896
Restricted Stock [Member] | Incentive Award Plan 2015 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of nonvested shares	189,000		189,000
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	61,445

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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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-Publisher FASB
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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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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 forfeited.

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For net-share settlement of share-based awards when the employer settles employees' income tax withholding obligations, this element represents the number of shares the employees use to repay the employer.

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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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