Entity Shell Company Entity Shell Company Class B Common Stock Common Class B [Member] Entity Filer Category Entity Filer Category Local Phone Number Local Phone Number Class of Stock [Domain] Class of Stock [Domain] Document Information [Line Items] Document Information [Line Items] Entity Public Float Entity Public Float ICFR Auditor Attestation Flag ICFR Auditor Attestation Flag Amendment Flag Amendment Flag Documents Incorporated by Reference Documents Incorporated by Reference [Text Block] Entity Emerging Growth Company Entity Emerging Growth Company Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Entity Current Reporting Status Entity Current Reporting Status Entity File Number Entity File Number Entity Small Business Entity Small Business Security Exchange Name Security Exchange Name Document Financial Statement Error Correction [Flag] Document Financial Statement Error Correction [Flag] Entity Address, State or Province Entity Address, State or Province Document Transition Report Document Transition Report Entity Address, Address Line One Entity Address, Address Line One Entity Address, Address Line Two Entity Address, Address Line Two City Area Code City Area Code Document Fiscal Period Focus Document Fiscal Period Focus Entity Voluntary Filers Entity Voluntary Filers Cover [Abstract] Cover [Abstract] Document Period End Date Document Period End Date Document Information [Table] Document Information [Table] Current Fiscal Year End Date Current Fiscal Year End Date Class of Stock [Axis] Class of Stock [Axis] Entity Central Index Key Entity Central Index Key Class A Common Stock Common Class A [Member] Entity Tax Identification Number Entity Tax Identification Number Document Annual Report Document Annual Report Entity Well-known Seasoned Issuer Entity Well-known Seasoned Issuer Amendment Description Amendment Description Entity Registrant Name Entity Registrant Name Trading Symbol Trading Symbol Document Fiscal Year Focus Document Fiscal Year Focus Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Title of 12(b) Security Title of 12(b) Security Entity Address, Postal Zip Code Entity Address, Postal Zip Code Entity Address, City or Town Entity Address, City or Town Document Type Document Type Entity Interactive Data Current Entity Interactive Data Current