CONSOLIDATED BALANCE SHEETS (Unaudited) (Parenthetical) - USD ($) $ in Millions	Sep. 30, 2015	Dec. 31, 2014
Current assets:
Allowance for doubtful accounts	$ 1.4	$ 1.4
Stockholders' equity:
Common Stock, par or stated value per share (in dollars per share)	$ 0.01	$ 0.01
Common Stock, shares authorized (in shares)	200,000,000	200,000,000
Common Stock, shares issued (in shares)	35,367,264	35,367,264
Treasury stock, shares (in shares)	1,669,346	1,757,997