Condensed Consolidated Statements of Stockholders' Deficit (Unaudited) - USD ($)	Common Stock [Member]	Additional Paid-in Capital [Member]	AOCI Attributable to Parent [Member]	Retained Earnings [Member]	Total
Balance at Dec. 31, 2022		$ 378,200,000	$ 50,800,000	$ (514,600,000)	$ (85,600,000)
Balance, shares at Dec. 31, 2022	25,909,516
Foreign currency translation adjustments			(2,900,000)		(2,900,000)
Actuarial gains on pension plan			200,000		200,000
Issuances under stock plans
Issuances under stock plans, shares	353,554
Stock-based compensation expense		3,000,000.0			3,000,000.0
Net loss				(1,400,000)	(1,400,000)
Reclassification of loss on hedging instrument to comprehensive income			200,000		200,000
Balance at Mar. 31, 2023		381,200,000	48,300,000	(516,000,000.0)	(86,500,000)
Balance, shares at Mar. 31, 2023	26,263,070
Balance at Dec. 31, 2023		386,100,000	44,500,000	(508,600,000)	(78,000,000.0)
Balance, shares at Dec. 31, 2023	26,219,021
Foreign currency translation adjustments			1,000,000.0		1,000,000.0
Actuarial gains on pension plan			300,000		300,000
Issuances under stock plans		(800,000)			(800,000)
Issuances under stock plans, shares	340,735
Stock-based compensation expense		2,000,000.0			2,000,000.0
Net loss				(5,700,000)	(5,700,000)
Balance at Mar. 31, 2024		$ 387,300,000	$ 45,800,000	$ (514,300,000)	$ (81,200,000)
Balance, shares at Mar. 31, 2024	26,559,756