Employee Benefit Plans - Net Periodic Benefit Costs (Details) - Pension Plan - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2017	Mar. 31, 2016
Components of net periodic (benefit) costs:
Service cost	$ 846	$ 924	$ 2,583	$ 2,865
Interest cost	3,686	4,837	11,326	15,419
Expected return on plan assets	(4,722)	(5,745)	(14,508)	(18,315)
Net periodic (benefit) cost	$ (190)	$ 16	$ (599)	$ (31)