Common Stock Repurchase Plan (Narrative) (Details) - USD ($)		6 Months Ended	8 Months Ended
	Jul. 29, 2016	Jun. 30, 2017	Mar. 31, 2017
Equity Class Of Treasury Stock [Line Items]
Shares repurchase program, repurchased cost		$ 70,900,000
Common Stock [Member]
Equity Class Of Treasury Stock [Line Items]
Shares repurchase program, expiration date	Jul. 31, 2018
Shares repurchase program, shares repurchased		1,659,452	2,800,000
Shares repurchase program, repurchased cost			$ 114,700,000
Shares repurchase program, average price per share		$ 42.60	$ 41.34
Common Stock [Member] | Maximum [Member]
Equity Class Of Treasury Stock [Line Items]
Shares repurchase program, authorized amount	$ 150,000,000