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Share-Based Compensation Plans (Details 2) (USD $) | 12 Months Ended |  |  |
--- | --- | --- | --- | ---
Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2010 | Dec. 31, 2009
Share-Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Abstract] |  |  |  |
Number of Options Outstanding | 47,000 | 71,597 | 145,209 | 213,103
Weighted Average Remaining Contractual Life (in years) | 4 years 10 months 10 days |  |  |
Number of Options Exercisable | 47,000 |  |  |
Weighted Average Exercise Price Per Share Outstanding | $ 23.19 |  |  |
Weighted Average Exercise Price Per Share Exercisable | $ 23.19 |  |  |
Range One [Member] |  |  |  |
Share-Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Abstract] |  |  |  |
Range of Exercise Prices Per Share, Lower Limit | $ 10.31 |  |  |
Number of Options Outstanding | 7,000 |  |  |
Weighted Average Remaining Contractual Life (in years) | 4 months 10 days |  |  |
Number of Options Exercisable | 7,000 |  |  |
Weighted Average Exercise Price Per Share Outstanding | $ 10.31 |  |  |
Weighted Average Exercise Price Per Share Exercisable | $ 10.31 |  |  |
Range Two [Member] |  |  |  |
Share-Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Abstract] |  |  |  |
Range of Exercise Prices Per Share | $ 14.00 |  |  |
Number of Options Outstanding | 2,000 |  |  |
Weighted Average Remaining Contractual Life (in years) | 1 year 4 months 10 days |  |  |
Number of Options Exercisable | 2,000 |  |  |
Weighted Average Exercise Price Per Share Outstanding | $ 14.00 |  |  |
Weighted Average Exercise Price Per Share Exercisable | $ 14.00 |  |  |
Range Three [Member] |  |  |  |
Share-Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Abstract] |  |  |  |
Range of Exercise Prices Per Share, Lower Limit | $ 22.07 |  |  |
Range of Exercise Prices Per Share, Upper Limit | $ 24.15 |  |  |
Number of Options Outstanding | 28,000 |  |  |
Weighted Average Remaining Contractual Life (in years) | 6 years 6 months 18 days |  |  |
Number of Options Exercisable | 28,000 |  |  |
Weighted Average Exercise Price Per Share Outstanding | $ 23.85 |  |  |
Weighted Average Exercise Price Per Share Exercisable | $ 23.85 |  |  |
Range Four [Member] |  |  |  |
Share-Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Abstract] |  |  |  |
Range of Exercise Prices Per Share | $ 28.31 |  |  |
Number of Options Outstanding | 4,000 |  |  |
Weighted Average Remaining Contractual Life (in years) | 3 years 4 months 10 days |  |  |
Number of Options Exercisable | 4,000 |  |  |
Weighted Average Exercise Price Per Share Outstanding | $ 28.31 |  |  |
Weighted Average Exercise Price Per Share Exercisable | $ 28.31 |  |  |
Range Five [Member] |  |  |  |
Share-Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Abstract] |  |  |  |
Range of Exercise Prices Per Share | $ 34.77 |  |  |
Number of Options Outstanding | 6,000 |  |  |
Weighted Average Remaining Contractual Life (in years) | 4 years 4 months 28 days |  |  |
Number of Options Exercisable | 6,000 |  |  |
Weighted Average Exercise Price Per Share Outstanding | $ 34.77 |  |  |
Weighted Average Exercise Price Per Share Exercisable | $ 34.77 |  |  |

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- Definition Share based compensation shares authorized under stock option plans exercise price range. + References No definition available. + Details
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- Definition The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option 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)(1)(iii) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 123R -Paragraph A240 -Subparagraph b(1)(c), d(2) -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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- Definition The number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding as of the balance sheet date, including vested options. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 123R -Paragraph A240 -Subparagraph b(1)(b) -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 3: 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)-(ii) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 123R -Paragraph A240 -Subparagraph b(1)(a) -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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- Definition Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding. + 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)(iii) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 123R -Paragraph 64 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices. + 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)-(ii) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 123R -Paragraph 64 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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