Employee Benefit Plans (Details) (USD $)	3 Months Ended		12 Months Ended
	Dec. 31, 2010	Sep. 30, 2010	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Employee Benefit Plans [Abstract]
Defined Benefit Plan, Service Cost			$ 0	$ 2,226,000	$ 1,499,000
Defined Benefit Plan, Interest Cost			269,000	3,323,000	5,997,000
Defined Benefit Plan, Amortization of Gains (Losses)			109,000	4,891,000	1,000,000
Defined Benefit Plan, Actual Return on Plan Assets			(241,000)	(224,000)	(242,000)
Defined Contribution Plan, Cost Recognized			6,500,000	5,600,000	6,600,000
defined benefit plan, notes payable due to employees	75,000,000			75,000,000
Rabbi Trust Fair Value Disclosure	86,000,000			86,000,000
Defined Benefit Plan, Benefits Paid			75,000,000	58,000,000
Agreed upon separation agreement % interest earned on unpaid benefits for former President and Senior VP and Secretary			8.75%
gain on rabbi trust assets sold	3,600,000
Defined Benefit Plan, Net Periodic Benefit Cost			137,000	10,216,000	8,254,000
Benefit Plan Termination and Related Costs		25,000,000	0	25,187,000	0
Defined Benefit Plan, net periodic pension cost and benefit plan termination and related costs			137,000	35,403,000	8,254,000
Defined Benefit Plan, Actuarial Net (Gains) Losses			1,145,000	(49,463,000)	40,342,000
Defined Benefit Plan, Amortization of Net Gains (Losses)			(110,000)	(4,891,000)	(1,000,000)
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax			1,035,000	(54,354,000)	39,342,000
Other Comprehensive Income (Loss), Reclassification, Pension and Other Postretirement Benefit Plans, Net Gain (Loss) Recognized in Net Periodic Benefit Cost, before Tax			1,172,000	(18,951,000)	47,596,000
percent of salary maximum contribution employee stock purchase plan			6.00%
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate	3.80%		5.40%	3.80%	5.60%
Actualrial Assumptions used to calulate benefit obligation, discount rate	5.40%		4.30%	5.40%	3.80%
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Adjustment, before Tax				23,300,000
future loss in other comprehensive income as a result of net periodic pension cost			300,000
Actuarial assumption used to calculate benefit obligation, expected rate of return on assets	6.00%		6.00%	6.00%	6.00%
maximum contribution to employee stock purchase plan			20,000
Actuarial Assumption used to calculated benefit obligation, rate of increase in compensation					15.00%
Defined Benefit Plan, Pension Plans with Accumulated Benefit Obligations in Excess of Plan Assets, Aggregate Projected Benefit Obligation			$ 300,000