Pension Plan and Employee Benefits Pension Plan and Employee Benefits, 401 (K) Plans (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
401(k) Plan [Abstract]
401 (k) Plan expense	$ 847	$ 852	$ 2,341	$ 2,053
Other Subsidiaries [Member]
401(k) Plan [Abstract]
401 (k) Plan expense	$ 200	$ 200	$ 600	$ 500