Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) $ in Millions	Sep. 30, 2017	Dec. 31, 2016
Statement of Financial Position [Abstract]
Accounts receivable, allowance	$ 0.9	$ 0.5
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	80,000,000	80,000,000
Common stock, shares issued	22,130,368	21,712,216
Treasury stock, shares	226,576	79,149