Share based compensation arrangement by share based payment award equity instruments other than options weighted average remaining life.

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- Definition

As of the balance-sheet date, the aggregate unrecognized cost of share-based awards made to employees under share-based compensation plans that have yet to vest.

+ References

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

+ Details

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- Definition

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)

+ Details

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- Definition

The total dollar difference between fair values of the underlying shares reserved for issuance and exercise prices pertaining to options outstanding under the plan as of the balance-sheet date.

+ References

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

+ Details

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Stock Incentive Plans (Components of the Restricted Stock Awards) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	Jun. 30, 2011	Dec. 31, 2010	Jun. 30, 2010	Dec. 31, 2009
Unvested awards	1,553,353	1,309,489	1,260,285	854,440
Unrecognized compensation expense	$ 6,933
Intrinsic value	16,077
Weighted average remaining life (in years)	2.50
Service-Based Awards [Member]
Unvested awards	563,747
Unrecognized compensation expense	2,315
Intrinsic value	5,835
Weighted average remaining life (in years)	2.21
Performance Based Awards [Member]
Unvested awards	989,606
Unrecognized compensation expense	4,618
Intrinsic value	$ 10,242
Weighted average remaining life (in years)	2.67