INVESTMENTS (Details) (USD $)	Apr. 30, 2014	Apr. 30, 2013
INVESTMENTS
Net unrealized gain	$ 1,700,000	$ 2,900,000
Carrying value of investments on deposit with various state insurance departments	7,400,000	7,400,000
Debt securities outstanding maturities at cost
Less than one year	6,155,000
Year two through year five	5,193,000
Year six through year ten	6,448,000
After ten years	158,000
Total debt securities outstanding amortized, cost	17,954,000
Debt securities outstanding maturities measured at fair value
Less than one year	6,191,000
Year two through year five	5,482,000
Year six through year ten	6,959,000
After ten years	194,000
Total debt securities outstanding measured at fair value	18,826,000
Cost
INVESTMENTS
Available for Sale Securities, Amortized Cost	19,655,000	25,051,000
Fair Value
INVESTMENTS
Available for Sale Securities Noncurrent, Fair Value	21,312,000	27,938,000
U.S. Treasury securities \| Cost
INVESTMENTS
Available for Sale Securities, Amortized Cost	9,257,000	18,145,000
U.S. Treasury securities \| Fair Value
INVESTMENTS
Available for Sale Securities Noncurrent, Fair Value	9,941,000	19,572,000
U.S. government agency securities \| Cost
INVESTMENTS
Available for Sale Securities, Amortized Cost	1,975,000	2,632,000
U.S. government agency securities \| Fair Value
INVESTMENTS
Available for Sale Securities Noncurrent, Fair Value	2,044,000	2,800,000
Corporate bonds and notes \| Cost
INVESTMENTS
Available for Sale Securities, Amortized Cost	6,722,000	773,000
Corporate bonds and notes \| Fair Value
INVESTMENTS
Available for Sale Securities Noncurrent, Fair Value	6,841,000	866,000
Corporate equity securities \| Cost
INVESTMENTS
Available for Sale Securities, Amortized Cost	1,701,000	3,501,000
Corporate equity securities \| Fair Value
INVESTMENTS
Available for Sale Securities Noncurrent, Fair Value	$ 2,486,000	$ 4,700,000

Carrying amount of cash and investment securities on deposit with state regulatory authorities in connection with capital requirements.

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