Long-Term Debt (Schedule Of Maturities On Long-Term Debt) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Debt Instrument [Line Items]
2013	$ 460,825
2014	279,538
2015	318,057
2016	405,923
2017	38,346
Thereafter	767,073
Long-term debt, excluding associated hedges	2,269,762
Long-term debt (less fair value hedges)	2,273,575	2,337,113
Parent Company [Member]
Debt Instrument [Line Items]
2013	385,771
2014	279,482
2015	318,004
2016	405,865
2017	38,285
Thereafter	591,400
Long-term debt, excluding associated hedges	$ 2,018,807