v2.4.0.6

Earnings Per Share (Narrative) (Details) (USD $)
In Millions, except Share data, unless otherwise specified

3 Months Ended

1 Months Ended

3 Months Ended

3 Months Ended

Mar. 31, 2013

Mar. 31, 2012

Dec. 31, 2012

Jun. 30, 2012

3.75% Convertible Notes [Member]

Mar. 31, 2012

3.75% Convertible Notes [Member]

Mar. 31, 2013

3.75% Convertible Notes [Member]

Mar. 31, 2013

2.50% convertible senior notes due August 15, 2013 [Member]

Mar. 31, 2012

2.50% convertible senior notes due August 15, 2013 [Member]

Mar. 31, 2008

2.50% convertible senior notes due August 15, 2013 [Member]

Mar. 31, 2013

Restricted stock and PSU's [Member]

Mar. 31, 2012

Restricted stock and PSU's [Member]

Mar. 31, 2013

Common stock [Member]

Mar. 31, 2012

Common stock [Member]

Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]

Stock options to purchase shares

7,125,748

^[1]

7,545,777

^[1]

4,934,596

4,671,407

7,125,748

9,676,899

Weighted average number diluted shares outstanding

3,958,437

4,517,573

4,816,000

4,510,278

5,855,220

7,140,309

Incremental common shares attributable to conversion of debt securities

34,482

^[2]

34,482

34,482

Debt instrument, interest rate

3.75%

3.75%

3.75%

2.50%

2.50%

2.50%

Debt instrument, principal outstanding

$ 0.5

$ 475.0

[1]	No stock option awards were granted during the three months ended March 31, 2013.
[2]	In June 2012, the remaining $0.5 million of our 3.75% convertible notes outstanding was converted into 34,482 shares of common stock in accordance with the terms of the notes.

X

- Definition

Including current and noncurrent portions, aggregate carrying amount of long-term borrowings as of the balance sheet date before deducting unamortized discount or premiums (if any). May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 9



Reference 2: http://www.xbrl.org/2003/role/presentationRef

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

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-Paragraph 20

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

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

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X

- Definition

Interest rate stated in the contractual debt agreement.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

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- Definition

Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of convertible debt securities using the if-converted method.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 260

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257



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-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.

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- Definition

Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

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-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257



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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.

+ References

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

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-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.



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