Stock Compensation Plans (Narrative) (Details)	0 Months Ended
Mar. 08, 2011
ICE Plan [Member]
Restricted shares granted	67,620
Performance shares granted	188,480
Number of shares granted under the plan	256,100
Upper Limit [Member]
Maximum payout ratio	200.00%
Maximum payout ratio, prior years	150.00%
Lower Limit [Member]
Minimum payout ratio	0.00%

Share Based Goods and Nonemployee Services Transaction Valuation Method, Maximum Range of Payout Rate

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Share Based Goods And Nonemployee Services Transaction Valuation Method Maximum Range Of Payout Rate, Prior Years

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Share Based Goods and Nonemployee Services Transaction Valuation Method, Minimum Range of Payout Rate

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- Definition

Stock Issued During Period Share Performance Stock Award Gross

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Net number of share options (or share units) granted during the period.

+ 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)(d)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iv)(1)

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Total number of shares issued during the period, including shares forfeited, as a result of Restricted Stock Awards.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

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-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 12

-Paragraph 10

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 129

-Paragraph 4, 5

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

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