Equity-Based Compensation (Schedule of Number of Awards and Weighted Average Grant Date Fair Value) (Details) - $ / shares	9 Months Ended
Sep. 30, 2015	Sep. 30, 2014
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Awards	174,919	168,857
Weighted Average Grant Date Fair Value	$ 16.13	$ 17.17
Restricted shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Awards	21,318	21,721
Weighted Average Grant Date Fair Value	$ 17.48	$ 16.76
Performance stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Awards	321,714
Weighted Average Grant Date Fair Value	$ 18.46

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).

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 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).

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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.

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