Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Statement of Financial Position [Abstract]
Allowance for doubtful accounts	$ 3.6	$ 3.5
Current maturities and loan origination fees	5.1	0.5
Premium on notes payable		2.5
Debt issuance costs on notes payable	$ 7.7	$ 7.8
Preferred stock, shares authorized	300,000.0	300,000.0
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, shares authorized	50,000,000	50,000,000
Common stock, shares issued	15,400,000	16,500,000
Common stock, shares outstanding	15,400,000	16,500,000