Acquisition of RSI Home Products, Inc. (the "RSI Acquisition") (Supplemental Pro Forma Financial Information) (Details) - RSI Home Products, Inc. [Member] $ / shares in Units, $ in Thousands	12 Months Ended
	Apr. 30, 2018 USD ($) $ / shares
Business Acquisition [Line Items]
Net Sales	$ 1,613,663
Net Income	$ 67,388
Net earnings per share - basic (usd per share) | $ / shares	$ 3.83
Net earnings per share - diluted (usd per share) | $ / shares	$ 3.80
Pro Forma [Member]
Business Acquisition [Line Items]
Stock compensation expense	$ 17,500