Earnings Per Common Share Common Stock (Details)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Class A Common Stock [Member]
Common Stock, Voting Rights	1	1
Class B Common Stock [Member]
Common Stock, Voting Rights	10	10

Description of voting rights of common stock. Includes eligibility to vote and votes per share owned. Include also, if any, unusual voting rights.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21475-112644

Name:	us-gaap_CommonStockVotingRights
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration