Share-Based Compensation - Summary of Director Stock Units Activity (Details) - Non-employee Board of Director's Plan - $ / shares	12 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2015
Number of Units
Balance at the beginning of the period (in shares)	334,943	287,436	269,315
Granted (in shares)	27,285	40,323	24,668
Distributed (in shares)	(30,022)		(11,296)
Dividend equivalents (in shares)	6,347	7,184	4,749
Balance at the end of the period (in shares)	338,553	334,943	287,436
Weighted Average Grant Date Fair Value
Balance at the beginning of the period (in dollars per share)	$ 38.64	$ 35.48	$ 32.25
Granted (in dollars per share)	39.69	32.54	42.80
Distributed (in dollars per share)	34.19		31.79
Dividend equivalents (in dollars per share)	0.00	0.00	0.00
Balance at the end of the period (in dollars per share)	$ 42.47	$ 38.64	$ 35.48