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Benefit Plans (Narrative) (Details) (USD $) In Millions, unless otherwise specified | 3 Months Ended
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Mar. 31, 2014
Benefit Plans [Line Items] |
Unrecognized compensation cost | $ 11.9
Minimum [Member] |
Benefit Plans [Line Items] |
Unrecognized compensation cost recognized over a weighted average period | 1 year
Maximum [Member] |
Benefit Plans [Line Items] |
Unrecognized compensation cost recognized over a weighted average period | 2 years

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- Details
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Period Type: | duration

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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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Period Type: | instant

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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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