Significant Accounting Policies Significant Accounting Policies - Recently Issued Accounting Pronouncements (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total revenue	$ 195,769	$ 147,984	$ 140,423	$ 114,169
Interest and Other Income									$ 28,457	$ 231	$ 808
Excess Tax Benefit from Share-based Compensation, Operating Activities									0
Research and Development Expense											2,300
Accounting Standards Update 2014-09 (Topic 606) [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total revenue					$ 159,084	$ 127,759	$ 105,529	$ 126,487
Interest and Other Income										24,954	22,942
Excess Tax Benefit from Share-based Compensation, Operating Activities										0	$ 5,965
Accounting Standards Update 2016-09 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Increase (Decrease) in Income Taxes									$ 3,800	$ 3,000
EffectiveIncomeTaxRateReconciliationChangeInTaxRateDueToExcessTaxBenefitsRecognizedFromShareBasedCompensation									(1.00%)	1.00%
Accounting Standards Update 2018-15 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Computer software cost capitalized									$ 800
Research and Development Expense									100
Minimum | Accounting Standards Update 2016-02 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating Lease, Right-of-Use Asset	32,000								32,000
Operating Lease, Liability	32,000								32,000
Maximum | Accounting Standards Update 2016-02 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating Lease, Right-of-Use Asset	36,000								36,000
Operating Lease, Liability	$ 36,000								$ 36,000