Aggregate dividends declared during the period for each share of common stock outstanding.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Name:	us-gaap_CommonStockDividendsPerShareDeclared
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

Capital Stock and Dividends (Details) - $ / shares										12 Months Ended
Capital Stock and Dividends (Details) - $ / shares	Feb. 07, 2018	Nov. 06, 2017	Aug. 07, 2017	May 08, 2017	Feb. 08, 2017	Oct. 31, 2016	Aug. 01, 2016	May 02, 2016	Feb. 03, 2016	Dec. 30, 2017	Dec. 31, 2016	Dec. 26, 2015
Dividends
Common Stock, Dividends, Per Share, Declared		$ 0.27	$ 0.27	$ 0.27	$ 0.24	$ 0.24	$ 0.24	$ 0.24	$ 0.20	$ 1.05	$ 0.92	$ 0.76
Subsequent Event
Dividends
Common Stock, Dividends, Per Share, Declared	$ 0.27