Stockholders' Equity (Schedule Of Option Activity) (Details)	6 Months Ended	12 Months Ended
	Dec. 31, 2019 $ / shares shares	Jun. 30, 2019 $ / shares shares
Stockholders' Equity [Abstract]
Options, Outstanding at beginning of period | shares	1,260,114
Options, Granted | shares	162,180
Options, Exercised | shares	(226,773)
Options, Forfeited | shares	(4,342)
Options, Outstanding at end of period | shares	1,191,179	1,260,114
Options, Exercise price of granted options	$ 146.34
Options exercisable at end of period | shares	753,219
Weighted Average Exercise Price, Outstanding at beginning of period	$ 72.91
Weighted Average Exercise Price, Granted	146.34
Weighted Average Exercise Price, Exercised	53.39
Weighted Average Exercise Price, Forfeited	110.19
Weighted Average Exercise Price, Outstanding at end of period	86.49	$ 72.91
Weighted Average Exercise Price, Options exercisable at end of period	$ 69.96
Weighted Average Remaining Contractual Term in Years, Outstanding	4 years 9 months 18 days	4 years 4 months 24 days