Shareholders' Equity (Narrative) (Details) (USD $) In Millions, except Share data, unless otherwise specified	0 Months Ended	1 Months Ended			3 Months Ended		9 Months Ended
	Aug. 06, 2011	Oct. 31, 2012	Aug. 31, 2012	Jul. 31, 2011	Sep. 28, 2012	Sep. 30, 2011	Sep. 28, 2012	Sep. 30, 2011
Class Of Stock [Line Items]
Quarterly dividend declared per share		$ 0.12		$ 0.12	$ 0.12	$ 0.12	$ 0.36	$ 0.36
Paid dividends			$ 15.3
Stock repurchase program, authorized amount	$ 50
Stock repurchase program, expiration period			12 months
Price per share of repurchased stock					$ 9.27
Quarter Three [Member]
Class Of Stock [Line Items]
Dividend paid date							Aug. 24, 2012
Dividend record date							Aug. 14, 2012
Quarter Four [Member]
Class Of Stock [Line Items]
Dividend paid date							Nov. 23, 2012
Dividend record date							Nov. 13, 2012
Common Class A [Member]
Class Of Stock [Line Items]
Number of shares repurchased and retired							690,502