Employee Benefit Plans (Details) - USD ($)	6 Months Ended	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2017	Jun. 30, 2016	Jun. 30, 2015
Employee Benefit Plans
Maximum employees' contribution (as a percent)		100.00%
Matching contribution of first 6% of eligible employees' contributions (as a percent)		50.00%
Percentage of eligible employees' contributions matched by the company		6.00%
Company's contribution	$ 536,000	$ 982,000	$ 1,100,000	$ 875,000