Employment Expenses and Benefit Plans (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Defined Benefit Plan Disclosure [Line Items]
401(k) percent of match	4.00%
Annual contribution	$ 9,100,000
Stock purchase plan, percent of match	15.00%
Money Purchase Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of aggregate contribution for eligible employees		3.00%	3.00%
Money purchase pension plan expense		7,100,000	7,400,000
Stock Purchase Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Stock purchase plans compensation expense	$ 955,000	$ 4,100,000	$ 4,600,000