Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2015
Statement of Comprehensive Income [Abstract]
Net income	$ 66,854	$ 72,081	$ 92,555
Other comprehensive income (loss), net of tax:
Foreign currency translation gains (losses)	19	(10)	(9)
Unrealized gains (losses) on investments	(11)	5	(8)
Total other comprehensive income (loss)	8	(5)	(17)
Total comprehensive income	$ 66,862	$ 72,076	$ 92,538

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax, before reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.

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