Consolidated Statements of Changes in Equity and Comprehensive Income (Unaudited) (Parenthetical) (USD $)	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010
Other comprehensive income:
Other comprehensive income, derivatives qualifying as hedges, tax effect	$ 50,884,000	$ 69,053,000
Other comprehensive income, defined benefit plans, tax	4,704,000	4,777,000
Other comprehensive income, available-for-sale securities, tax	24,014,000	28,421,000
Other comprehensive income, foreign currency translation adjustment, tax	226,000	135,000
Preferred dividends on subsidiaries' preferred stock	10,100,000	10,100,000
Accumulated Other Comprehensive Income (Loss)
Other comprehensive income:
Other comprehensive income, derivatives qualifying as hedges, tax effect	50,884,000	69,053,000
Other comprehensive income, defined benefit plans, tax	4,704,000	4,777,000
Other comprehensive income, available-for-sale securities, tax	24,014,000	28,421,000
Other comprehensive income, foreign currency translation adjustment, tax	$ 226,000	$ 135,000

Equity impact of preferred stock cash dividends declared by an entity during the period. This element includes paid and unpaid dividends declared during the period.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 405

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6957935&loc=d3e64057-112817

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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

-Publisher AICPA

-Name Statement of Position (SOP)

-Number 01-6

-Paragraph 14

-Subparagraph l

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=6959260&loc=d3e187085-122770

+ Details

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- Definition

Tax effect of the gross appreciation or the gross loss, net of reclassification adjustment, in the value of the total unsold available-for-sale securities at the end of an accounting period.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 130

-Paragraph 25

-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 220

-SubTopic 10

-Section 45

-Paragraph 12

-URI http://asc.fasb.org/extlink&oid=6920043&loc=d3e640-108580

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

-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 51

-Paragraph 38

-Subparagraph c(3)

-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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Period Type:	duration

- Definition

Tax effects of the increase (decrease) to accumulated comprehensive income during the period related to benefit plans. While for technical reasons this element has no balance attribute, the default assumption is a credit balance consistent with its label.

+ References

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- Definition

Total tax effect of the change in accumulated gains and losses from derivative instruments designated and qualifying as the effective portion of cash flow hedges. The change includes an entity's share of an equity investee's increase or decrease in deferred hedging gains or losses. While for technical reasons this element has no balance attribute, the default assumption is a credit balance consistent with its label.

+ References

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- Definition

Tax effect of the adjustment that results from the process of translating subsidiary financial statements and foreign equity investments into functional currency of the reporting entity. While for technical reasons this element has no balance attribute, the default assumption is a credit balance consistent with its label.

+ References

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