CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Retained Earnings	Unearned ESOP Shares	Accumulated Other Comprehensive Income (Loss)
Beginning Balance (in shares) at Jun. 30, 2014		16,562,450
Beginning Balance at Jun. 30, 2014	$ 114,864	$ 16,562	$ 35,917	$ 106,212	$ (16,035)	$ (27,792)
Net income	652			652
Unrealized losses on cash flow hedges, net of reclassifications to earnings	(18,506)					(18,506)
Change in the funded status of retiree benefit obligations, net of tax	(14,122)					(14,122)
ESOP compensation expense, including reclassifications	4,424		(377)		4,801
Share-based compensation (in shares)		4,272
Share based compensation	1,267	$ 4	1,263
Stock option exercises (in shares)		95,723
Stock option exercises	$ 1,548	$ 96	1,452
Shares withheld to cover taxes (in shares)	(4,297)
Shares withheld to cover taxes	$ (116)	$ (4)	(112)
Ending Balance (in shares) at Jun. 30, 2015		16,658,148
Ending Balance at Jun. 30, 2015	90,011	$ 16,658	38,143	106,864	(11,234)	(60,420)
Net income	89,918			89,918
Unrealized losses on cash flow hedges, net of reclassifications to earnings	8,249					8,249
Change in the funded status of retiree benefit obligations, net of tax	(11,461)					(11,461)
ESOP compensation expense, including reclassifications	3,387		(1,413)		4,800
Share-based compensation (in shares)		1,551
Share based compensation	956	$ 2	954
Stock option exercises (in shares)		127,039
Stock option exercises	$ 1,693	$ 127	1,566
Shares withheld to cover taxes (in shares)	(5,177)
Shares withheld to cover taxes	$ (159)	$ (5)	(154)
Ending Balance (in shares) at Jun. 30, 2016		16,781,561
Ending Balance at Jun. 30, 2016	182,594	$ 16,782	39,096	196,782	(6,434)	(63,632)
Net income	24,400			24,400
Unrealized losses on cash flow hedges, net of reclassifications to earnings	(3,933)					(3,933)
Change in the funded status of retiree benefit obligations, net of tax	7,466					7,466
ESOP compensation expense, including reclassifications	2,487		342		2,145
Share-based compensation (in shares)		(889)
Share based compensation	1,472	$ (1)	1,473
Stock option exercises (in shares)		82,803
Stock option exercises	$ 687	$ 83	604
Shares withheld to cover taxes (in shares)	(17,473)
Shares withheld to cover taxes	$ (38)	$ (18)	(20)
Ending Balance (in shares) at Jun. 30, 2017		16,846,002
Ending Balance at Jun. 30, 2017	$ 215,135	$ 16,846	$ 41,495	$ 221,182	$ (4,289)	$ (60,099)