Supplemental Disclosures (Schedule of Cash Flow, Supplemental Disclosures and Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Jul. 15, 2015	Aug. 15, 2014
Non-cash financing activities:
Capital expenditures in accounts payable and other liabilities	$ 102.2	$ 108.5	$ 55.8
Equipment acquired or refinanced through capital leases	12.5	14.5	3.8
Cash (received) paid for:
Interest income	(1.1)	(1.5)	(1.3)
Interest expense	28.4	25.7	24.8
Income taxes	20.0	18.1	$ 12.9
Aptina [Member]
Cash (received) paid for:
Consideration placed in escrow	18.8	40.0			$ 40.0
Consideration released from escrow	21.2
Restricted Cash and Cash Equivalents		$ 40.0
AXSEM [Member]
Cash (received) paid for:
Consideration placed in escrow	$ 0.8			$ 0.8