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Stock-Based Compensation (Schedule of Performance Unit Awards) (Details) (USD $) | 0 Months Ended | 12 Months Ended
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Mar. 15, 2011 | Dec. 31, 2013 Incentive Plan, 2011-2013 [Member] Performance Shares [Member] | Dec. 31, 2013 Incentive Plan, 2012-2014 [Member] Performance Shares [Member] | Dec. 31, 2013 Incentive Plan, 2013-2015 [Member] Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Grant Date |  | March 15, 2011 | March 6, 2012 | February 27, 2013
Units |  | 34,002 | 43,042 | 31,418
Grant Date Fair Value | $ 38.46 | $ 38.46 | $ 27.49 | $ 42.49
Aggregate Fair Value |  | $ 1,308,000 | $ 1,183,000 | $ 1,335,000

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- Definition Fair value of equity-based compensation awards outstanding. + References No definition available. + Details
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- Definition Grant date of stock-based compensation. + References No definition available. + Details
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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=6415400&loc=d3e5070-113901 + Details
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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 + Details
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