Operating Leases, as Lessee (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Operating Leased Assets [Line Items]
Rent expense under operating leases	$ 20.1	$ 14.6	$ 5.9
Capitalized rent	$ 0.1
Santa Clara [Member]
Operating Leased Assets [Line Items]
Sublease expiration period	2052-10