Comprehensive Income - Components of comprehensive income that are included in Consolidated Statement of Changes in Shareholders' Equity (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Oct. 31, 2014	Oct. 31, 2013	Oct. 31, 2014	Oct. 31, 2013
Comprehensive Income (Loss) Note [Abstract]
Change in unrealized gains on securities, Before Tax			$ (27)	$ 61
Change in unrealized gains on securities, Tax (Expense) Benefit			10	(21)
Change in unrealized gains on securities, Net of Tax			(17)	40
Other comprehensive income (loss), available-for-sale securities adjustment, Before Tax			(27)	61
Other comprehensive income (loss), available-for-sale securities, Tax (Expense) Benefit			10	(21)
Other comprehensive income (loss), available-for-sale securities adjustment, Net of Tax	$ 68	$ 42	$ (17)	$ 40