Fair Value (Carrying Value And Estimated Fair Value Of Financial Instruments) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Carrying Value [Member] | Level 2 [Member]
Fair Value and Carrying Value, by Balance Sheet Grouping [Line Items]
Long-term debt	$ 951,000	$ 951,000
Carrying Value [Member] | Level 3 [Member]
Fair Value and Carrying Value, by Balance Sheet Grouping [Line Items]
Long-term debt	342,000	302,000
Carrying Value [Member] | Level 3 [Member] | Affiliated Entity [Member]
Fair Value and Carrying Value, by Balance Sheet Grouping [Line Items]
Long-term debt	51,547	51,547
Carrying Value [Member] | Level 3 [Member] | Nonrecourse Long-Term Debt [Member]
Fair Value and Carrying Value, by Balance Sheet Grouping [Line Items]
Long-term debt	17,838	32,803
Estimated Fair Value [Member] | Level 2 [Member]
Fair Value and Carrying Value, by Balance Sheet Grouping [Line Items]
Long-term debt	1,054,512	1,164,639
Estimated Fair Value [Member] | Level 3 [Member]
Fair Value and Carrying Value, by Balance Sheet Grouping [Line Items]
Long-term debt	329,581	320,892
Estimated Fair Value [Member] | Level 3 [Member] | Affiliated Entity [Member]
Fair Value and Carrying Value, by Balance Sheet Grouping [Line Items]
Long-term debt	37,114	43,686
Estimated Fair Value [Member] | Level 3 [Member] | Nonrecourse Long-Term Debt [Member]
Fair Value and Carrying Value, by Balance Sheet Grouping [Line Items]
Long-term debt	$ 18,636	$ 35,297