CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (Parenthetical) - $ / shares	3 Months Ended	12 Months Ended
Dec. 31, 2019	Sep. 29, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jul. 01, 2018	Apr. 01, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Common stock
Dividends paid per share (USD per share)	$ 0.773	$ 0.773	$ 0.722	$ 0.722	$ 0.722	$ 0.722	$ 0.656	$ 0.656	$ 2.990	$ 2.756	$ 2.548
Class B common stock
Dividends paid per share (USD per share)	$ 0.702	$ 0.702	$ 0.656	$ 0.656	$ 0.656	$ 0.656	$ 0.596	$ 0.596	$ 2.716	$ 2.504	$ 2.316

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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

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