Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017
Net income	$ 9,405	$ 7,378	$ 20,281	$ 18,335
Other comprehensive income (loss):
Available-for-sale securities, Pre-tax	41	(44)	15	(30)
Available-for-sale securities, Tax	(11)	17	(4)	12
Available-for-sale securities, Net of Tax	30	(27)	11	(18)
Postemployment severance actuarial change, Pre-tax	158	239	238	506
Postemployment severance actuarial change, Tax	(41)	(84)	(61)	(188)
Postemployment severance actuarial change, Net of Tax	117	155	177	318
Derivative gain (loss), Pre-tax	(2)	0	(11)	0
Derivative gain (loss), Tax	0	0	2	0
Derivative gain (loss), Net of Tax	(2)	0	(9)	0
Reclassification to (earnings) loss:
Available-for-sale securities, Pre-tax	0	3	0	3
Available-for-sale securities, Tax	0	(1)	0	(1)
Available-for-sale securities, Net of Tax	0	2	0	2
Amortization of actuarial change, Pre-tax	(103)	(66)	(202)	(133)
Amortization of actuarial change, Tax	27	17	52	43
Amortization of actuarial change, Net of Tax	(76)	(49)	(150)	(90)
Derivatives, Pre-tax	5	0	21	0
Derivatives, Tax	(1)	0	(5)	0
Derivatives, Net of Tax	4	0	16	0
Other comprehensive income (loss), Pre-tax	99	132	61	346
Other comprehensive income (loss), Tax	(26)	(51)	(16)	(134)
Other comprehensive income (loss), Net of Tax	73	81	45	212
Total comprehensive income	$ 9,478	$ 7,459	$ 20,326	$ 18,547