Consolidated Statements of Shareholders' Equity - 3 months ended Jul. 31, 2020 - USD ($) $ in Thousands	Total	COMMON STOCK	RETAINED EARNINGS	ACCUMULATED OTHER COMPREHENSIVE LOSS
Balance at beginning of period (shares) at Apr. 30, 2020	16,926,537	16,926,537
Balance at beginning of period at Apr. 30, 2020	$ 700,538	$ 359,430	$ 392,281	$ (51,173)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	$ 16,485
Stock repurchases (shares)	0
Balance at end of period (shares) at Jul. 31, 2020	16,988,340
Balance at end of period at Jul. 31, 2020	$ 721,520