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Benefit Plans (Narrative) (Details) $ in Millions | 6 Months Ended
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Jun. 30, 2016 USD ($) shares
Defined Benefit Plan Disclosure [Line Items] |
Unrecognized compensation cost | $ | $ 11.2
Minimum [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Unrecognized compensation cost recognized over a weighted average period | 1 year
Maximum [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Unrecognized compensation cost recognized over a weighted average period | 2 years
Performance Restricted Stock Unit And Performance Restricted Unit [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Performance period | 3 years
Actual number of shares paid out upon vesting, minimum percentage of target shares | 0.00%
Actual number of shares paid out upon vesting, maximum percentage of target shares | 200.00%
Performance Units [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Instrument valuation based on shares of common stock, number of shares | 1
Performance Restricted Stock Unit [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Instrument valuation based on shares of common stock, number of shares | 1
Performance Restricted Unit [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Instrument valuation based on shares of common stock, number of shares | 1
Key Employee Performance Restricted Unit [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Instrument valuation based on shares of common stock, number of shares | 1
Restricted Stock Unit And Restricted Unit [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Instrument valuation based on shares of common stock, number of shares | 1
Performance period | 3 years

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- Definition Unrecognized cost of unvested share-based compensation awards. + 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 (i) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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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. + 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 (i) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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