Country Region Country Region Document Type Document Type Common Class C [Member] Common Class C [Member] City Area Code City Area Code Amendment Flag Amendment Flag Soliciting Material Soliciting Material Document Period End Date Document Period End Date Entity Tax Identification Number Entity Tax Identification Number Pre-commencement Tender Offer Pre-commencement Tender Offer Entities [Table] Entities [Table] Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Entity Address, Country Entity Address, Country Class of Stock [Domain] Class of Stock [Domain] Class of Stock [Axis] Class of Stock [Axis] Entity File Number Entity File Number Entity Central Index Key Entity Central Index Key Trading Symbol Trading Symbol Common Class B [Member] Common Class B [Member] Entity Address, Postal Zip Code Entity Address, Postal Zip Code Local Phone Number Local Phone Number Written Communications Written Communications Title of 12(b) Security Title of 12(b) Security Security Exchange Name Security Exchange Name Entity Address, City or Town Entity Address, City or Town Cover [Abstract] Pre-commencement Issuer Tender Offer Pre-commencement Issuer Tender Offer Common Class A [Member] Common Class A [Member] Entity Address, Address Line One Entity Address, Address Line One Entity Address, Address Line Two Entity Address, Address Line Two Entity Emerging Growth Company Entity Emerging Growth Company Entity Registrant Name Entity Registrant Name Entity Information [Line Items] Entity Information [Line Items]