Investments In Securities Held To Maturity (Details) $ in Thousands	Mar. 31, 2017 USD ($)
Schedule of Held-to-maturity Securities [Line Items]
Cost	$ 2,961
Gross Unrealized Gains	1
Gross Unrealized Losses	(1)
Fair Market Value	2,961
Fixed Income Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Cost	1,315
Gross Unrealized Gains	0
Gross Unrealized Losses	(1)
Fair Market Value	1,314
Mutual Fund [Member]
Schedule of Held-to-maturity Securities [Line Items]
Cost	0
Gross Unrealized Gains	0
Gross Unrealized Losses	0
Fair Market Value	0
Commercial Paper [Member]
Schedule of Held-to-maturity Securities [Line Items]
Cost	1,646
Gross Unrealized Gains	1
Gross Unrealized Losses	0
Fair Market Value	$ 1,647