Significant Accounting Policies Major Components of Inventories (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Accounting Policies [Abstract]
Raw materials and purchased components	$ 208,501	$ 194,108
Service parts, garments and accessories	320,396	307,684
Finished goods	443,039	329,288
Less: reserves	(46,693)	(47,119)
Inventories	$ 925,243	$ 783,961