Long Term Performance Share Plan [Member]

No definition available.

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- Definition

Share Based Compensation Arrangement by Share Based Payment Award, Options, Expiration Term

+ References

No definition available.

+ Details

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ 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 (h)(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 Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph g(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section F

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph 64

-Subparagraph 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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 14.F)

-URI http://asc.fasb.org/extlink&oid=6793087&loc=d3e301413-122809

+ Details

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- Definition

Aggregate number of common shares reserved for future issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 129

-Paragraph 4

-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 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.29)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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- Definition

Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

+ References

No definition available.

+ Details

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- Definition

Percentage of employer's matching contributions to a defined contribution plan that vests in a given year.

+ References

No definition available.

+ 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

+ Details

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- Definition

Aggregate unrecognized cost of share-based awards, other than options, made to employees under an equity-based compensation plan, that have yet to vest.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Aggregate unrecognized cost of option awards made to employees under a stock option plan or plans, that have yet to vest.

+ References

No definition available.

+ Details

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

The discount rate from market value on offering date that participants pay for shares.

+ References

Reference 1: 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

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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

+ Details

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- Definition

The total accumulated difference between fair values of underlying shares on dates of exercise and exercise price on options which were exercised (or share units converted) into shares during the reporting period under the plan.

+ References

+ Details

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Stock-Based Compensation Plans (Additional Information) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of total compensation	4.00%
Stock Option and Incentive Plan 2003 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of shares of stock reserved and available for issuance	800,000
Stock based compensation, option granted, contractual life	10 years
Stock Option and Incentive Plan 2012 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of shares of stock reserved and available for issuance	800,000
Stock based compensation, vesting period	5 years
Stock based compensation, option granted, contractual life	10 years
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation	$ 99	$ 204	$ 182
Forfeiture rate	5.00%
Unrecognized compensation cost for nonvested stock options	360
Unrecognized compensation cost, recognition period	2 years 9 months 18 days
Total intrinsic value of options exercised	146	16	56
Restricted Stock Awards and Management Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation	228	129	91
Unrecognized compensation cost related to nonvested shares	219
Unrecognized compensation cost, recognition period	1 year
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation, vesting period	3 years
Share-based compensation	163	92	72
Stock based compensation, shares granted	7,050
Management Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation, vesting period	2 years
Share-based compensation	65	37	19
Stock based compensation, shares granted	7,195
Long-Term Performance Share Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation	174	672	526
Unrecognized compensation cost related to nonvested shares	314
Unrecognized compensation cost, recognition period	11 months 1 day
Stock based compensation, shares granted	22,627
Deferred Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation	37	20	10
Unrecognized compensation cost related to nonvested shares	$ 176
Unrecognized compensation cost, recognition period	14 years
Percentage of total compensation	10.00%
Percentage vested on 65th birthday	100.00%
Stock based compensation, shares granted	2,322	2,135
Qualified Stock Options [Member] \| Stock Option and Incentive Plan 2003 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price as a percentage of fair market value on the date of grant	100.00%
Qualified Stock Options [Member] \| Stock Option and Incentive Plan 2012 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price as a percentage of fair market value on the date of grant	100.00%
Nonqualified Stock Options [Member] \| Stock Option and Incentive Plan 2003 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price as a percentage of fair market value on the date of grant	85.00%
Nonqualified Stock Options [Member] \| Stock Option and Incentive Plan 2012 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price as a percentage of fair market value on the date of grant	85.00%