Credit Facility (Summary Of Outstanding Letters Of Credit And/Or Borrowings) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Line of Credit Facility [Line Items]
Commitment	$ 150,000	$ 150,000
In use	851	1,551
Citibank Holdings Credit Facility [Member]
Line of Credit Facility [Line Items]
Commitment	150,000	150,000
Revolving Credit Borrowings [Member]
Line of Credit Facility [Line Items]
In use
Letters Of Credit [Member]
Line of Credit Facility [Line Items]
In use	$ 851	$ 1,551
Maturity/Expiry Date	Dec. 31, 2014	Dec. 31, 2013