Inventories (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Inventories [Abstract]
Terms of precious metals consignment agreements, maximum			1 year
Fees under precious metals consignment agreements	$ 0.2	$ 0.2	$ 0.4	$ 0.4
Fair value of precious metals on hand under consignment agreements	$ 26.7		$ 26.7		$ 26.6