Derivative Financial Instruments (Schedule Of Foreign Currency Derivative) (Details) In Millions		9 Months Ended
Sep. 30, 2011 CAD	Sep. 30, 2011 Contract Type [Member]
Notional Amount of Foreign Currency Derivatives	305
Maturity of Foreign Currency Derivatives	December 30, 2011
Foreign Exchange Fixed Rate Received	0.96150
Investment Foreign Currency, Contract, Transaction Type Flag		Sell

- Definition

The entity's designation of its position on the foreign currency contract being described. This flag can only have the values of "Buy" or "Sell".

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

+ Details

Name:	invest_InvestmentForeignCurrencyContractTransactionTypeFlag
Namespace Prefix:	invest
Data Type:	invest:foreignCurrencyContractTransactionItemType
Balance Type:	na
Period Type:	duration

- Definition

The contractual rate at which a foreign currency can be purchased or sold under the terms of a foreign currency derivative contract.

+ Details

Name:	us-gaap_DerivativeForwardExchangeRate
Namespace Prefix:	us-gaap
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	instant

- Definition

Date when foreign currency exchange rate derivatives mature or expire.

+ Details

Name:	us-gaap_MaturityOfForeignCurrencyDerivatives
Namespace Prefix:	us-gaap
Data Type:	us-types:durationStringItemType
Balance Type:	na
Period Type:	instant

- Definition

Aggregate notional amount of foreign currency exchange rate derivatives. Notional amount refers to the number of currency units specified in the foreign currency derivative contract.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Notional Amount

-URI http://asc.fasb.org/extlink&oid=6519104

+ Details

Name:	us-gaap_NotionalAmountOfForeignCurrencyDerivatives
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant