Shareholders' Equity (Narrative) (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
Shareholders Equity [Line Items]
Treasury stock, value	$ 0		$ 0		$ 763,120,000
Stock-based compensation expense	8,800,000	8,500,000	23,200,000	31,300,000
Unrecognized compensation cost	59,400,000		59,400,000
Employee Stock Option [Member]
Shareholders Equity [Line Items]
Requisite service period			2 years
Restricted Stock [Member]
Shareholders Equity [Line Items]
Requisite service period			6 months
Restricted Stock Units (RSUs) [Member]
Shareholders Equity [Line Items]
Requisite service period			2 years 1 month 6 days
Restatement Adjustment [Member]
Shareholders Equity [Line Items]
Additional paid in capital, common stock	1,500,000		1,500,000
Treasury stock, value	$ 763,100,000		$ 763,100,000