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Stock-Based Compensation (Stock Appreciation Rights Award Activity) (Details) - $ / shares | 12 Months Ended
--- | ---
Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
SARs, Weighted Average Exercise Price [Roll Forward] |  |  |
Stock-Settled SARs, Outstanding | 101,006 |  |
Cash-Settled SARs, Outstanding | 131,924 |  |
Stock Appreciation Rights (SARs) [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Awards, expiration period | 10 years |  |
SARs Activity [Roll Forward] |  |  |
Outstanding, Beginning | 297,714 | 375,104 | 389,686
Granted | 12,356 | 7,733 | 132,566
Exercised | (77,140) | (85,123) | (147,148)
Outstanding, Ending | 232,930 | 297,714 | 375,104
Exercisable | 112,295 | 88,751 | 56,938
SARs, Weighted Average Exercise Price [Roll Forward] |  |  |
Oustanding, Beginning (in usd per share) | $ 25.20 | $ 24.03 | $ 20.81
Granted (in usd per share) | 57.25 | 47.74 | 29.56
Exercised (in usd per share) | 22.52 | 22.09 | 20.47
Oustanding, Ending (in usd per share) | 27.79 | 25.20 | 24.03
Exercisable (in usd per share) | $ 24.60 | $ 23.15 | $ 20.95

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- Definition Number of non-option equity instruments exercised by participants. + 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)(1)(iv)(2) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Net number of non-option equity instruments granted to participants. + 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)(1)(iv)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Number of equity instruments other than options outstanding, including both vested and non-vested instruments. + 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)(1)(i) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(ii) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Period from grant date that an equity-based award expires, 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 (a)(2) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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