CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY (USD $) In Thousands, unless otherwise specified	Preferred Stock Convertible	Common Stock	Additional Paid-In Capital	Retained Earnings	Other Comprehensive Gain (Loss)	Total
Balance at Mar. 31, 2012	$ 9	$ 20		$ 81,108	$ 44	$ 81,181
Balance (in shares) at Mar. 31, 2012	3	20,338
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of restricted stock, net
Issuance of restricted stock, net (in shares)		168
Share based compensation			1,943			1,943
Dividends declared				(32,080)		(32,080)
Repurchased and retired shares			(3,865)			(3,865)
Repurchased and retired shares (in shares)		(397)
Deferred tax adjustment related to restricted stock			(284)			(284)
Allocation of retirement of repurchased shares of additional paid in capital and retained earnings			2,206	(2,206)
Net income				17,165	17,165	17,165
Other comprehensive loss:
Net Change in unrealized loss on short term investments					(46)	(46)
Total comprehensive income					17,119	17,119
Balance at Mar. 31, 2013	9	20		63,987	(2)	64,014
Balance (in shares) at Mar. 31, 2013	3	20,109
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of restricted stock, net
Issuance of restricted stock, net (in shares)		81
Share based compensation			1,479			1,479
Dividends declared				(13,312)		(13,312)
Deferred tax adjustment related to restricted stock			99			99
Net income				17,972	17,972	17,972
Other comprehensive loss:
Net Change in unrealized loss on short term investments					(35)	(35)
Total comprehensive income					17,937	17,937
Balance at Mar. 31, 2014	9	20	1,578	68,647	(37)	70,217
Balance (in shares) at Mar. 31, 2014	3	20,190
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of restricted stock, net
Issuance of restricted stock, net (in shares)		72
Share based compensation			1,481			1,481
Dividends declared				(13,757)		(13,757)
Deferred tax adjustment related to restricted stock			58			58
Net income				17,453	17,453	17,453
Other comprehensive loss:
Net Change in unrealized loss on short term investments					(17)	(17)
Total comprehensive income					17,436	17,436
Balance at Mar. 31, 2015	$ 9	$ 20	$ 3,117	$ 72,343	$ (54)	$ 75,435
Balance (in shares) at Mar. 31, 2015	3	20,262