Consolidated Statements of Stockholders' Equity - USD ($) shares in Thousands, $ in Thousands	Cumulative Effect, Period of Adoption, Adjustment [Member] Common Stock [Member]	Cumulative Effect, Period of Adoption, Adjustment [Member] Additional Paid-in Capital [Member]	Cumulative Effect, Period of Adoption, Adjustment [Member] Retained Earnings [Member]	Cumulative Effect, Period of Adoption, Adjustment [Member] AOCI Attributable to Parent [Member]	Cumulative Effect, Period of Adoption, Adjustment [Member] Treasury Stock [Member]	Cumulative Effect, Period of Adoption, Adjustment [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	AOCI Attributable to Parent [Member]	Treasury Stock [Member]	Total
Adoption of ASC 606							$ 41,976	$ 61,328	$ 761,430	$ (121,859)	$ (292,080)	$ 450,795
Balance at Jun. 30, 2018							41,976	61,328	761,430	(121,859)	$ (292,080)	450,795
Balance (in shares) at Jun. 30, 2018											15,279
Stock issued for employee stock option and purchase plans, including related income tax benefit and other							0	(234)	0	0	$ 1,186	952
Stock issued for employee stock option and purchase plans, including related income tax benefit and other (in shares)											(62)
Stock-based compensation							0	2,680	0	0	$ 0	2,680
Treasury stock acquired							0	0	0	0	$ (19,239)	(19,239)
Treasury stock acquired (in shares)											236
Adoption of ASC 606	$ 0	$ 0	$ (1,106)	$ 0	$ 0	$ (1,106)	41,976	63,774	808,417	(124,417)	$ (310,133)	479,617
Net Income							0	0	55,521	0	0	55,521
Foreign currency translation adjustment							0	0	0	(5,252)	0	(5,252)
Pension and OPEB adjustments, net of tax							0	0	0	2,754	0	2,754
Change in fair value of derivatives, net of tax							0	0	0	(60)	0	(60)
Dividends declared							0	0	(7,428)	0	0	(7,428)
Balance at Mar. 31, 2019	0	0	(1,106)	0	0	(1,106)	41,976	63,774	808,417	(124,417)	$ (310,133)	479,617
Balance (in shares) at Mar. 31, 2019											15,453
Adoption of ASC 606							41,976	63,024	784,687	(126,777)	$ (310,084)	452,826
Balance at Dec. 31, 2018							41,976	63,024	784,687	(126,777)	$ (310,084)	452,826
Balance (in shares) at Dec. 31, 2018											15,454
Stock issued for employee stock option and purchase plans, including related income tax benefit and other							0	99	0	0	$ 55	154
Stock issued for employee stock option and purchase plans, including related income tax benefit and other (in shares)											(2)
Stock-based compensation							0	651	0	0	$ 0	651
Treasury stock acquired							0	0	0	0	$ (104)	(104)
Treasury stock acquired (in shares)											1
Adoption of ASC 606	0	0	(1,106)	0	0	(1,106)	41,976	63,024	784,687	(126,777)	$ (310,084)	452,826
Net Income							0	0	26,269	0	0	26,269
Foreign currency translation adjustment							0	0	0	410	0	410
Pension and OPEB adjustments, net of tax							0	0	0	813	0	813
Change in fair value of derivatives, net of tax							0	0	0	1,137	0	1,137
Dividends declared							0	0	(2,539)	0	0	(2,539)
Balance at Mar. 31, 2019	0	0	(1,106)	0	0	(1,106)	41,976	63,774	808,417	(124,417)	$ (310,133)	479,617
Balance (in shares) at Mar. 31, 2019											15,453
Adoption of ASC 606	0	0	(1,106)	0	0	(1,106)	41,976	63,774	808,417	(124,417)	$ (310,133)	479,617
Adoption of ASC 606							41,976	65,515	818,282	(137,278)	(324,182)	464,313
Balance at Jun. 30, 2019							41,976	65,515	818,282	(137,278)	$ (324,182)	464,313
Balance (in shares) at Jun. 30, 2019											15,650
Stock issued for employee stock option and purchase plans, including related income tax benefit and other							0	110	0	0	$ 1,468	1,578
Stock issued for employee stock option and purchase plans, including related income tax benefit and other (in shares)											(71)
Stock-based compensation							0	5,285	0	0	$ 0	5,285
Treasury stock acquired							0	0	0	0	$ (9,008)	(9,008)
Treasury stock acquired (in shares)											142
Adoption of ASC 606	0	0	(55)	0	0	(55)	41,976	70,910	828,556	(142,916)	$ (331,722)	466,804
Net Income							0	0	18,353	0	0	18,353
Foreign currency translation adjustment							0	0	0	(5,860)	0	(5,860)
Pension and OPEB adjustments, net of tax							0	0	0	3,519	0	3,519
Change in fair value of derivatives, net of tax							0	0	0	(3,297)	0	(3,297)
Dividends declared							0	0	(8,024)	0	0	(8,024)
Balance at Mar. 31, 2020	0	0	(55)	0	0	(55)	41,976	70,910	828,556	(142,916)	$ (331,722)	466,804
Balance (in shares) at Mar. 31, 2020											15,721
Adoption of ASC 606							41,976	70,206	837,698	(136,404)	$ (323,872)	489,604
Balance at Dec. 31, 2019							41,976	70,206	837,698	(136,404)	$ (323,872)	489,604
Balance (in shares) at Dec. 31, 2019											15,602
Stock issued for employee stock option and purchase plans, including related income tax benefit and other							0	238	0	0	$ 212	450
Stock issued for employee stock option and purchase plans, including related income tax benefit and other (in shares)											(10)
Stock-based compensation							0	466	0	0	$ 0	466
Treasury stock acquired							0	0	0	0	$ (8,062)	(8,062)
Treasury stock acquired (in shares)											129
Adoption of ASC 606	0	0	(55)	0	0	(55)	41,976	70,206	837,698	(136,404)	$ (323,872)	489,604
Net Income							0	0	(6,323)	0	0	(6,323)
Foreign currency translation adjustment							0	0	0	(4,691)	0	(4,691)
Pension and OPEB adjustments, net of tax							0	0	0	1,321	0	1,321
Change in fair value of derivatives, net of tax							0	0	0	(3,142)	0	(3,142)
Dividends declared							0	0	(2,764)	0	0	(2,764)
Balance at Mar. 31, 2020	0	0	(55)	0	0	(55)	41,976	70,910	828,556	(142,916)	$ (331,722)	466,804
Balance (in shares) at Mar. 31, 2020											15,721
Adoption of ASC 606	$ 0	$ 0	$ (55)	$ 0	$ 0	$ (55)	$ 41,976	$ 70,910	$ 828,556	$ (142,916)	$ (331,722)	$ 466,804