Debt (Cash Convertible Notes) (Narrative) (Details) (Cash Convertible Notes, USD $)	12 Months Ended	6 Months Ended
	Dec. 31, 2013	Jun. 30, 2014 Convertible Debt	Dec. 31, 2013 Convertible Debt	Sep. 15, 2008 Convertible Debt
Debt Instrument [Line Items]
Trading days	20 days
Consecutive trading days	30 days
Ratio of observed share price to conversion reference price		130.00%
Conversion reference price		$ 13.32
Outstanding principal		$ 574,000,000	$ 574,000,000	$ 575,000,000
Reference principal amount		$ 1,000
Conversion reference rate, per reference principal amount		75.0751