Consolidated Statements of Equity - USD ($) $ in Millions	Total	Common Stock	Additional Paid-in-Capital	Accumulated Other Comprehensive Loss	Company Shares Held by SERP	Retained Earnings	Noncontrolling Interest
Balance (in shares) at Dec. 31, 2021		22,767,052
Balance at Dec. 31, 2021	$ 651.3	$ 4.5	$ 130.6	$ (32.4)	$ (1.2)	$ 549.3	$ 0.5
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	4.1					4.1
Other comprehensive income	4.2			4.1			0.1
Dividends	(2.8)					(2.8)
Share-based compensation	1.8		1.8
Issuance of common stock under incentive plan (in shares)		69,995
Issuance of common stock under incentive plan	0.1	$ 0.1	0.0
Withholding tax paid upon equity award vesting	(1.3)		(1.3)
Balance (in shares) at Mar. 31, 2022		22,837,047
Balance at Mar. 31, 2022	$ 657.4	$ 4.6	131.1	(28.3)	(1.2)	550.6	0.6
Balance (in shares) at Dec. 31, 2022	22,624,031	22,624,031
Balance at Dec. 31, 2022	$ 626.9	$ 4.5	135.8	(40.1)	(1.1)	527.8	0.0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	12.1					12.1	0.0
Other comprehensive income	0.1			0.0			0.1
Dividends	(2.9)		0.0			(2.9)
Share-based compensation	0.8		0.8
Issuance of common stock under incentive plan (in shares)		66,536
Issuance of common stock under incentive plan	0.0	$ 0.0	0.0
Withholding tax paid upon equity award vesting	$ (1.4)		(1.4)
Balance (in shares) at Mar. 31, 2023	22,690,567	22,690,567
Balance at Mar. 31, 2023	$ 635.6	$ 4.5	$ 135.2	$ (40.1)	$ (1.1)	$ 537.0	$ 0.1