Other Income (Expense) Other Income (Expense) (Narrative) (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended			3 Months Ended	1 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013 Align Technology, Inc.	Feb. 28, 2013 Apex
Marketable securities, number of shares sold				5
Marketable securities, number of shares received in a legal settlement				8
Proceeds from sale of marketable equity securities	$ 251.2	$ 0	$ 0	$ 251.0
Gain on sale of marketable equity securities	201.5	0	0	202.0
Marketable securities, after tax realized gain (loss)				125
After-tax gain on sale upon closing of transaction, per diluted share				$ 0.18
Pre-tax gain on sale of unconsolidated joint venture	$ 229.8	$ 0	$ 0		$ 229.8