Maximum number of share to be delivered upon measurement period relative to shareholder return.

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Number of shares to be issued under deferred compensation plan included in shares outstanding.

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Share Based And Deferred Compensation Textuals Abstract.

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Share Based Compensation Arrangement By Share Based Payment Award Plan Modification Decremental Compensation Cost.

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Share Based Compensation Arrangement By Share Based Payment Award Terms Of Purchase Common Shares.

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Share Based Compensation Arrangement By Share Based Payment Stock Options Nonvested Number.

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Share Based Compensation Arrangement Maximum Contributions By Plan Participants.

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Voluntary termination of employment terms.

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Represents the expense recognized during the period arising from share-based compensation arrangements (for example, shares of stock, 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 Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph 64
-Subparagraph b

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Statement of Financial Accounting Standard (FAS)
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 14
-Section F

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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As of the latest balance-sheet date presented, the total compensation cost related to outstanding, nonvested share-based compensation awards not yet recognized (will be charged against earnings as services are performed or other vesting criteria are met).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
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The weighted average period over which unrecognized share-based compensation costs are expected to be reported.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
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-Subparagraph h

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Reflects the dating as to when the share-based award expires as specified in the award agreement, which may be presented in a variety of ways (for example, year, month and year, day, month and year, quarter of a year).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph a

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Description of the period of time over 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, which may be expressed in a variety of ways (for example, in years, month and year).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph a

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The number of outstanding awards on nonstock option plans (for example, phantom stock plan, stock appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares.

+ 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(2)(a)

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph b(2)(b)

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- Definition

The total fair value of share-based awards for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares, other instruments, or cash in accordance with the terms of the arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
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-Paragraph A240
-Subparagraph c(2)

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The maximum number of shares originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the share-based compensation plan. As stock options and equity instruments other than options are awarded to participants, the shares remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph a

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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.

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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)(a)

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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
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An excess of the fair value of the modified award over the fair value of the award immediately before the modification.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph g(2)

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- Definition

The average of prices paid for shares purchased on the open market for issuance to employees under the plan.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph 64, 65

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240

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Share Based and Deferred Compensation (Details Textuals) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended									1 Months Ended	3 Months Ended		6 Months Ended		1 Months Ended	3 Months Ended		6 Months Ended			1 Months Ended	3 Months Ended		6 Months Ended			3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010	Dec. 31, 2010	Mar. 02, 2011 Executive Officer [Member] Restricted Share Awards [Member]	May 24, 2011 Executive Officer [Member] Stock Option [Member]	Mar. 02, 2011 Executive Officer [Member] Stock Option [Member]	Mar. 02, 2011 Executive Officer [Member] Restricted Performance Share Units Plan [Member]	Mar. 04, 2010 Executive Officer [Member] Restricted Performance Share Units Plan [Member]	Apr. 01, 2009 Executive Officer [Member] Restricted Performance Share Units Plan [Member]	Mar. 31, 2011 Stock Option [Member]	Jun. 30, 2011 Stock Option [Member]	Jun. 30, 2010 Stock Option [Member]	Jun. 30, 2011 Stock Option [Member]	Jun. 30, 2010 Stock Option [Member]	Mar. 31, 2011 Restricted Share Awards [Member]	Jun. 30, 2011 Restricted Share Awards [Member]	Jun. 30, 2010 Restricted Share Awards [Member]	Jun. 30, 2011 Restricted Share Awards [Member]	Jun. 30, 2010 Restricted Share Awards [Member]	Dec. 31, 2010 Restricted Share Awards [Member]	Mar. 31, 2011 Restricted Performance Share Units Plan [Member]	Jun. 30, 2011 Restricted Performance Share Units Plan [Member]	Jun. 30, 2010 Restricted Performance Share Units Plan [Member]	Jun. 30, 2011 Restricted Performance Share Units Plan [Member]	Jun. 30, 2010 Restricted Performance Share Units Plan [Member]	Jun. 30, 2009 Restricted Performance Share Units Plan [Member]	Jun. 30, 2011 Outperformance Program [Member]	Jun. 30, 2010 Outperformance Program [Member]	Jun. 30, 2011 Outperformance Program [Member]	Jun. 30, 2010 Outperformance Program [Member]	Jun. 30, 2011 Employee Share Purchase Plan [Member]	Jun. 30, 2010 Employee Share Purchase Plan [Member]	Jun. 30, 2011 Employee Share Purchase Plan [Member]	Jun. 30, 2010 Employee Share Purchase Plan [Member]	Jun. 30, 2011 Deferred Compensation Plan [Member]	Jun. 30, 2010 Deferred Compensation Plan [Member]
Share Based and Deferred Compensation (Textuals) [Abstract]
Options outstanding under equity incentive plan	3,642,965		3,642,965		3,116,611								3,642,965		3,642,965
Unvested options													1,311,943		1,311,943
Unrecognized compensation expenses													$ 3.1		$ 3.1			$ 5.1		$ 5.1
Weighted average period over which options will be recognized															2.0					1.6
Compensation expense recognized	1.6	1.8	3.3	3.1									0.4	0.3	0.7	0.5		0.8	1.0	1.6	1.8			0.5	0.3	0.8	0.5		0.1	0.1	0.1	0.2	0.1	0.2	0.1	0.2
Restricted shares outstanding																		808,763		808,763		851,278
Vesting Period															over three years		after three years from the grant date			three to seven years from initial grant date						3
Share-based Compensation Arrangement by Share-based Payment Award, Award Expiration Dating			10 Years
Employee Service Share-based Compensation, Capitalized Amount	0.4	0.4	0.7	0.6									0.1		0.2			0.1	0.2	0.3	0.4			0.1		0.2
Aggregate share-based awards awarded to executives						174,012	101,437	603,241	124,293	120,955	488,292																						1,250,000		1,250,000
Voluntary termination of employment Terms												after reaching age 57 and accumulating at least 15 years of service with the Company					after reaching age 57 and accumulating at least 15 years of service with the Company						after reaching age 57 and accumulating at least 15 years of service with the Company
Maximum number of shares to be delivered at the end of the measurement period relative to the total shareholder return																										equal a certain percentage (not to exceed 200%) of the participant’s base units
Fair value of awards on the grant date																										2.0	2.0	1.1			5.9
Share purchases made by employees under ESPP																																			85% of the average closing price per share for a specified period
Maximum participant contribution under 2011 plan																																			limited to the lesser of 20% of compensation or $50,000
Purchase price of shares purchased under ESPP																																	0.1	0.2	0.2	0.3
Net increase in compensation costs due to change in market value of participant investment in plan																																					0.4	0.2
Net decrease in compensation costs due to change in market value of participant investment in plan																																					$ 0.4	$ 0.2
Number of shares to be issued under deferred compensation plan included in total shares outstanding																																					300,000	300,000