Share-Based Compensation Arrangements (Nonvested Performance Shares) (Details) (Performance Based Nonvested Shares [Member], USD $)	3 Months Ended
Mar. 31, 2015
Performance Based Nonvested Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grant date fair value	$ 38.02
Award Vesting Period	3 years
Equity Instruments Other than Options Minimum Shares Earned to Target Percentage	0.00%
Equity Instruments Other than Options Maximum Shares Earned to Target Percentage	200.00%
Performance share awards, shares vesting percentage	150.00%
Performance share awards, shares vesting	46,950

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.

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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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued 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=6415400&loc=d3e5070-113901

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- Definition

The current assumption based on the most recent information available shares vesting percentage for performance nonvested equitybased awards.

+ References

No definition available.

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- Definition

Percent of shares earned to the target of equity instruments other than options, the maximum percentage of the range.

+ References

No definition available.

+ Details

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- Definition

Percent of shares earned to the target for equity instruments other than options, the minimum percentage of the range.

+ References

No definition available.

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- Definition

Shares vesting for performance nonvested equity based awards based on the most recent information available.

+ References

No definition available.

+ Details

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