Income Taxes (Narrative) (Details) - USD ($)	3 Months Ended	9 Months Ended	12 Months Ended
	Mar. 31, 2018	Dec. 31, 2017	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Operating Loss Carryforwards [Line Items]
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent			31.55%	35.00%	35.00%
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount			$ 1,109,000	$ 41,000	$ 1,905,000
Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Amount	$ 1,000,000	$ 2,500,000	1,500,000
Gross amounts of deferred tax assets	81,846,000		81,846,000	125,612,000
Valuation allowance	(4,671,000)		(4,671,000)	(4,585,000)
Foreign subsidiary income			25,144,000	3,071,000	5,448,000
Cumulative undistributed earnings of foreign subsidiaries	120,000,000		120,000,000
Income Tax Effects Allocated Directly to Equity, Employee Stock Options			1,230,000
Amount accrued for the payment of interest and penalties			33,000	21,000
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense			(197,000)
Federal
Operating Loss Carryforwards [Line Items]
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount			16,102,000
Foreign net operating losses	$ 3,837,000		$ 3,837,000	$ 4,370,000	$ 3,426,000
Scenario, Previously Reported [Member]
Operating Loss Carryforwards [Line Items]
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent			3500.00%
Scenario, Adjustment [Member]
Operating Loss Carryforwards [Line Items]
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent			2100.00%