Significant Accounting Policies Income Taxes (Details) - USD ($)	3 Months Ended		6 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Accounting Policies [Abstract]
Proceeds and Excess Tax Benefit from Share-based Compensation	$ 214,000		$ 1,120,000
Effective Income Tax Rate Reconciliation, Other Reconciling Items, Amount	$ 0.002		$ 0.005
Effective Income Tax Rate Reconciliation, Noncontrolling Interest Income (Loss), Percent	2.80%	6.70%	3.60%	4.40%
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount				$ 4,055,000
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Percent		3.50%		2.30%
Current Income Tax Expense (Benefit)				$ 2,200,000
Effective Income Tax Rate Reconciliation, Tax Settlement, Percent		1.90%		1.20%