This item represents the difference between the gross realized gains and losses realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. Additionally, this item would include any losses recognized for other than temporary impairments (OTTI) of the subject investments in debt and equity securities.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

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-Subparagraph (a)

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- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

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-Name Accounting Standards Codification

-Topic 470

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-Topic 470

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- Definition

Amount of the cost of borrowed funds accounted for as interest expense.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 20

-Section 50

-Paragraph 1

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-Name Accounting Standards Codification

-Topic 942

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-Paragraph 1

-Subparagraph (SX 210.9-04.9)

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-Name Regulation S-X (SX)

-Number 210

-Section 04

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- Definition

The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.7)

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-Name Regulation S-X (SX)

-Number 210

-Section 03

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The net result for the period of deducting operating expenses from operating revenues.

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No definition available.

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- Definition

Income (Loss) from continuing operations, including the portion attributable to noncontrolling interest, and income (loss) from equity method investments, but before extraordinary items, cumulative effects of changes in accounting principles and income taxes.

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No definition available.

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Segment And Geographic Information (Reconciliation Of Total Segment Income From Operations To Consolidated Income Before Income Taxes) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Segment Reporting [Abstract]
Income from operations for reportable segments	$ 302,387us-gaap_OperatingIncomeLoss	$ 306,761us-gaap_OperatingIncomeLoss	$ 266,788us-gaap_OperatingIncomeLoss	$ 248,055us-gaap_OperatingIncomeLoss	$ 257,580us-gaap_OperatingIncomeLoss	$ 266,602us-gaap_OperatingIncomeLoss	$ 235,227us-gaap_OperatingIncomeLoss	$ 194,055us-gaap_OperatingIncomeLoss	$ 1,123,991us-gaap_OperatingIncomeLoss	$ 953,464us-gaap_OperatingIncomeLoss	$ 615,351us-gaap_OperatingIncomeLoss
Interest expense									(37,352)us-gaap_InterestExpense	(18,082)us-gaap_InterestExpense	(43,049)us-gaap_InterestExpense
Debt retirement costs									0	0	(7,082)
Gain from sales of equity securities									0	0	16,429
Other income, (expense), net									(2,721)us-gaap_NonoperatingIncomeExpense	6,790us-gaap_NonoperatingIncomeExpense	3,520us-gaap_NonoperatingIncomeExpense
Income (Loss) from Continuing Operations before Income Taxes									$ 1,083,918	$ 942,172	$ 585,169