Stockholders' Equity - Additional Information (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands		12 Months Ended
	Sep. 30, 2006	Apr. 30, 2022	Apr. 24, 2021	Apr. 25, 2020	Apr. 25, 2015	Dec. 31, 2002	Mar. 13, 2013	Dec. 31, 1991
Shareholders Equity [Line Items]
common stock repurchased (in shares)		1,032	0	0
Common stock repurchased		$ 35,000
Average cost of common shares repurchased (in usd per share)		$ 33.90
Shares authorized for repurchase under share repurchase program (in shares)							500,000
Remaining shares available under repurchase program (in shares)		465,000
Hours of service completed in order to be allocated shares of stock acquired by plan		1000 hours
Number of shares allocated to ESOP (in shares)		9,551
Number of shares allocated to ESOP, Fair value		$ 293,879
ESOP share based compensation expense		$ 0	$ 9,265	$ 14,419
Thompson Dental Company
Shareholders Equity [Line Items]
Additional loan to ESOP						$ 12,612
ESOP acquiring shares during acquisition (in shares)						666
Interest due from ESOP					$ 200
Total shares allocated to ESOP (in shares)						98
Remaining shares in ESOP (in shares)						568
Committed-to-be-released (in shares)		0
Suspense shares (in shares)		0
1990 Note
Shareholders Equity [Line Items]
ESOP company loan								$ 22,000
2006 Senior Notes
Shareholders Equity [Line Items]
ESOP company loan	$ 105,000
ESOP acquiring shares during acquisition (in shares)	3,160				844
Contributed to ESOP					$ 20,214