Operating Segments (Reconciliation Of Reportable Segments Measure Of Profit Or Loss To Income) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2016
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Operating income	$ 10,072	$ 7,564	$ 16,307	$ 25,006	$ 14,726	$ 24,547	$ 25,589	$ 32,181	$ 58,949	$ 97,043	$ 114,368
Interest income									17,885	20,897	15,292
Interest expense									(8,941)	(3,484)	(3,423)
Income before income taxes									67,893	114,456	126,237
Reportable Segment [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Operating income									85,690	130,799	129,774
Corporate/Eliminations [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Operating income									$ (26,741)	$ (33,756)	$ (15,406)