Shareholders' Equity (Narrative) (Details) (USD $) Share data in Thousands, except Per Share data, unless otherwise specified	3 Months Ended			12 Months Ended			1 Months Ended	12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Jul. 31, 2013 Share repurchase plan [Member]	Dec. 31, 2013 Share repurchase plan [Member]	Dec. 31, 2013 Shares withheld to pay taxes [Member]	Dec. 31, 2012 Shares withheld to pay taxes [Member]	Dec. 31, 2011 Shares withheld to pay taxes [Member]
Class of Stock [Line Items]
Cash dividends declared (usd per share)	$ 0.05	$ 0.05	$ 0.05	$ 0.15	$ 0	$ 0
Remaining value of stock repurchase programs authorization				$ 234,300,000			$ 352,300,000
Shares repurchased under authorized repurchase programs								7,200
Stock repurchases				127,661,000	961,000	2,836,000		118,100,000	9,600,000	1,000,000	2,800,000
Stock repurchased under repurchase program during period, value					$ 0	$ 0