Cover page. Document type Document Type Document period end date Document Period End Date Entity registrant name Entity Registrant Name Amendment flag Amendment Flag Entity central index key Entity Central Index Key Entity incorporation, state Entity Incorporation, State or Country Code Entity file number Entity File Number Entity tax identification number Entity Tax Identification Number Entity address, address line one Entity Address, Address Line One Entity address, address line two Entity Address, Address Line Two Entity address, city Entity Address, City or Town Entity address, state Entity Address, State or Province Entity address, postal zip code Entity Address, Postal Zip Code City area code City Area Code Local phone number Local Phone Number Written communications Written Communications Soliciting material Soliciting Material Pre-commencement tender offer Pre-commencement Tender Offer Pre-commencement issuer tender offer Pre-commencement Issuer Tender Offer Entity emerging growth company Entity Emerging Growth Company Entity Listings [Table] Entity Listings [Table] Class of Stock [Axis] Class of Stock [Axis] Class of Stock [Domain] Class of Stock [Domain] Common stock Common Stock [Member] Preferred stock Preferred Stock [Member] Floating rate senior notes due 2022 Floating Rate Senior Notes Due 2022 [Member] Floating Rate Senior Notes Due 2022 Member [Member] 1.7% senior notes due 2022 1.7% Senior Notes Due 2022 [Member] 1.7% Senior Notes Due 2022 [Member] 2.5% senior notes due 2025 2.5% Senior Notes Due 2025 [Member] 2.5% Senior Notes Due 2025 [Member] 0.2% senior notes due 2026 0.2% Senior Notes Due 2026 [Member] 0.2% Senior Notes Due 2026 [Member] 1.2% senior notes due 2027 1.2% Senior Notes Due 2027 [Member] 1.2% Senior Notes Due 2027 [Member] 0.45% senior notes due 2028 0.45% Senior Notes Due 2028 [Member] 0.45% Senior Notes Due 2028 [Member] 0.75% senior notes due 2031 0.75% Senior Notes Due 2031 [Member] 0.75% Senior Notes Due 2031 [Member] 1.35% senior notes due 2039 1.35% Senior Notes Due 2039 [Member] 1.35% Senior Notes Due 2039 [Member] 1.8% senior notes due 2049 1.8% Senior Notes Due 2049 [Member] 1.8% Senior Notes Due 2049 [Member] Entity Listings [Line Items] Entity Listings [Line Items] Title of 12(b) security Title of 12(b) Security Trading symbol Trading Symbol Security exchange name Security Exchange Name