Employee Benefit Plans (Narrative) (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Compensation and Retirement Disclosure [Abstract]
Amount of each dollar matching contributed up to first four percent of individual base salary and incentive cash bonus			$ 1.00
Percentage of contribution of individual's base salary and incentive cash bonus			4.00%
Amount of each dollar matching contributed of next two percent of individual base salary and incentive cash bonus			0.50
Percentage of contribution of compensation			2.00%
Defined benefit plan, contributions by employer	$ 798,000	$ 601,000	$ 2,853,000	$ 2,206,000