Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		9 Months Ended		12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Jun. 30, 2018	Dec. 31, 2017	Mar. 31, 2018	Mar. 31, 2017	Jun. 30, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent				35.00%
Tax Cuts and Jobs Act Discrete Tax Expense					$ 4,300
Excess tax benefits from stock-based compensation					$ 0	$ 2,344
Effective income tax rate (as a percent)	23.70%	30.40%			28.20%	33.50%
Accounting Standards Update 2016-09 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Change in Effective Income Tax Rate Due to Excess Tax Benefits Recognized from Share-Based Compensation	(2.00%)				(1.00%)
Increase (Decrease) in Income Taxes	$ (1,200)				$ (2,100)
Scenario, Forecast [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent			21.00%				28.10%
Net Operating Loss [Member] | Scenario, Forecast [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Effective Income Tax Rate Reconciliation, Deduction, Percent			80.00%
Interest Expense [Member] | Scenario, Forecast [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Effective Income Tax Rate Reconciliation, Deduction, Percent			30.00%