Income Taxes (Summary Of Tax Credit Carryforwards) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011
Other Tax Carryforward [Line Items]
Total net operating loss amount	$ 214,195
Tax windfall	(1,853)
After limitations	212,342
Operating loss carryforward expiration year 2020
Other Tax Carryforward [Line Items]
Net operating loss amount	27,465
Operating loss carryforward expiration year 2021
Other Tax Carryforward [Line Items]
Net operating loss amount	50,430
Operating loss carryforward expiration year 2022
Other Tax Carryforward [Line Items]
Net operating loss amount	115,000
Operating loss carryforward expiration year 2023
Other Tax Carryforward [Line Items]
Net operating loss amount	5,712
Operating loss carryforward expiration year 2024
Other Tax Carryforward [Line Items]
Net operating loss amount	3,566
Operating loss carryforward expiration year 2025
Other Tax Carryforward [Line Items]
Net operating loss amount	1,707
Operating loss carryforward expiration year 2026
Other Tax Carryforward [Line Items]
Net operating loss amount	476
Operating loss carryforward expiration year 2028
Other Tax Carryforward [Line Items]
Net operating loss amount	1,360
Operating loss carryforward expiration year 2029
Other Tax Carryforward [Line Items]
Net operating loss amount	4,074
Operating loss carryforward expiration year 2030
Other Tax Carryforward [Line Items]
Net operating loss amount	$ 4,405