Incentive Plan (Summary Of Stock Options) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2011 years
Incentive Plan [Abstract]
Outstanding, beginning of period, Number of Options Granted	1,414,450
Options granted, Number of Options Granted
Options forfeited, Number of Options Granted	(5,000)
Options exercised, Number of Options Granted	(616,000)
Options expired, Number of Options Granted	(6,000)
Outstanding, end of period, Number of Options Granted	787,450
Exercisable, end of period, Number of Options Granted	764,450
Vested or expected to vest, end of period, Number of Options Granted	787,450
Outstanding, beginning of period, Weighted Average Exercise Price	$ 11.44
Options granted, Weighted Average Exercise Price
Options forfeited, Weighted Average Exercise Price	$ 6.98
Options exercised, Weighted Average Exercise Price	$ 7.36
Options expired, Weighted Average Exercise Price	$ 26.84
Outstanding, end of period, Weighted Average Exercise Price	$ 14.55
Exercisable, end of period, Weighted Average Exercise Price	$ 14.30
Vested or expected to vest, end of period, Weighted Average Exercise Price	$ 14.55
Outstanding, end of period, Weighted Average Remaining Contractual Term	3.47
Exercisable, end of period, Weighted Average Remaining Contractual Term	3.42
Vested or expected to vest, end of period, Weighted Average Remaining Contractual Term	3.47
Outstanding, end of period, Aggregate Intrinsic Value	$ 5,988
Exercisable, end of period, Aggregate Intrinsic Value	5,988
Vested or expected to vest, end of period, Aggregate Intrinsic Value	$ 5,988