Consolidated Statements of Shareholders' Equity - USD ($) $ in Millions		Total	Common Stock	Additional Paid-In Capital	Retained Earnings	Treasury Stock	Accumulated Other Comprehensive (Loss) Income	Noncontrolling Interest
Beginning balance (in shares) at Dec. 31, 2016			14,846,035
Beginning balance at Dec. 31, 2016		$ 236.0	$ 14.9	$ 108.8	$ 193.6	$ (48.6)	$ (42.7)	$ 10.0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income		54.3			28.6		24.8	0.9
Stock-based compensation		8.6		8.6
Restricted stock awards issued (in shares)			266,280
Restricted stock awards issued		0.0	$ 0.3	(0.3)
Restricted stock cancelled (in shares)			(2,000)
Restricted stock cancelled		0.0
Performance shares issued (in shares)			4,694
Performance shares issued		0.0
Exercise of stock options (in shares)			38,000
Exercise of stock options		0.7		0.7
Dividends		(6.9)			(6.3)			(0.6)
Purchase of treasury stock		(6.6)				(6.6)
Acquisition adjustment		1.7						1.7
Other		0.2			0.2
Ending balance (in shares) at Dec. 31, 2017			15,153,009
Ending balance at Dec. 31, 2017		$ 288.0	$ 15.2	117.8	216.1	(55.2)	(17.9)	12.0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cash dividends per common share (in dollars per share)		$ 0.5
Comprehensive income		$ 32.2			53.6		(23.0)	1.6
Stock-based compensation		8.3		8.3
Restricted stock awards issued (in shares)			410,100
Restricted stock awards issued		0.0	$ 0.4	(0.4)
Restricted stock cancelled (in shares)			(7,834)
Restricted stock cancelled		0.0
Dividends		(6.4)			(6.4)
Purchase of treasury stock		(12.1)				(12.1)
Ending balance (in shares) at Dec. 31, 2018			15,555,275
Ending balance at Dec. 31, 2018		$ 312.6	$ 15.6	125.7	265.9	(67.3)	(40.9)	13.6
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cash dividends per common share (in dollars per share)		$ 0.5
Comprehensive income		$ 43.6			38.6		3.9	1.1
Stock-based compensation		4.1		4.1
Restricted stock awards issued (in shares)	[1]		266,123
Restricted stock awards issued	[1]	0.1	$ 0.2	(0.1)
Restricted stock cancelled (in shares)			(115,000)
Restricted stock cancelled		0.0	$ (0.1)	0.1
Dividends		(7.0)			(6.3)			(0.7)
Purchase of treasury stock		(3.8)				(3.8)
Ending balance (in shares) at Dec. 31, 2019			15,706,398
Ending balance at Dec. 31, 2019		$ 349.6	$ 15.7	$ 129.8	$ 298.2	$ (71.1)	$ (37.0)	$ 14.0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cash dividends per common share (in dollars per share)		$ 0.5

[1] Includes 52,173 restricted share units converted to common stock.