Stock Based Compensation (Narrative) (Details) - Performance-based restricted stock units [Member] - $ / shares	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance-based shares available for vesting	0
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance-based shares available for vesting	400,000
2018 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting date	Mar. 31, 2021
Weighted average grant date fair value (in dollars per share)	$ 19.30
Award vesting period (in years)	3 years
Percent of performance measurement based on ROIC	50.00%
Percent of performance measurement based on Adjusted EPS	50.00%
Performance period (start date)	Jan. 01, 2018
Performance period (end date)	Dec. 31, 2020
2018 [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units granted	0
2018 [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units granted	200,000
2017 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting date		Mar. 31, 2020
Weighted average grant date fair value (in dollars per share)		$ 21.35
Award vesting period (in years)		3 years
Percent of performance measurement based on ROIC		50.00%
Percent of performance measurement based on Adjusted EPS		50.00%
Performance period (start date)		Jan. 01, 2017
Performance period (end date)		Dec. 31, 2019
2017 [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units granted		0
2017 [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units granted		200,000

Percent of performance measurement based on adjusted earnings per share (Adjusted EPS).

No definition available.

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- Definition

Percentage of performance measurement based on return on invested capital (ROIC).

+ References

No definition available.

+ Details

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- Definition

Amount of performance based shares that will be available for vesting.

+ References

No definition available.

+ Details

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- Definition

Ending date of period in which performance criteria are measured.

+ References

No definition available.

+ Details

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- Definition

Starting date of period in which performance criteria are measured.

+ References

No definition available.

+ Details

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- Definition

Date the equity-based award vests.

+ References

No definition available.

+ Details

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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

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=96867065&loc=d3e5070-113901

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

+ 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 (c)(2)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

+ Details

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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.

+ Details

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