Accumulated Other Comprehensive Loss (Details) $ in Thousands	6 Months Ended
	Dec. 31, 2020 USD ($)
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at June 30, 2020	$ (6,206)
Other comprehensive income (loss)	3,843
Effect of deferred taxes on unrealized losses	(942)
Effect of exchange rates on the pension plans	0
Net current period other comprehensive (loss) income	2,901
Balance at December 31, 2020	(3,305)
Pension and Postretirement Benefit Plans [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at June 30, 2020	(1,517)
Other comprehensive income (loss)	44
Effect of deferred taxes on unrealized losses	0
Effect of exchange rates on the pension plans	(138)
Net current period other comprehensive (loss) income	(94)
Balance at December 31, 2020	(1,611)
Currency Translation Adjustments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at June 30, 2020	523
Other comprehensive income (loss)	(379)
Effect of deferred taxes on unrealized losses	0
Effect of exchange rates on the pension plans	138
Net current period other comprehensive (loss) income	(241)
Balance at December 31, 2020	282
Unrealized Loss on Investments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at June 30, 2020	(5,212)
Other comprehensive income (loss)	4,178
Effect of deferred taxes on unrealized losses	(942)
Effect of exchange rates on the pension plans	0
Net current period other comprehensive (loss) income	3,236
Balance at December 31, 2020	$ (1,976)