Cover Page - USD ($) $ in Billions	12 Months Ended
	Dec. 31, 2019	Mar. 06, 2020
Entity Information [Line Items]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2019
Document Transition Report	false
Entity File Number	001-16441
Entity Registrant Name	CROWN CASTLE INTERNATIONAL CORP
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	76-0470458
Entity Address, Address Line One	1220 Augusta Drive
Entity Address, Address Line Two	Suite 600
Entity Address, City or Town	Houston
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	77057-2261
City Area Code	713
Local Phone Number	570-3000
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Public Float	$ 54.0
Entity Common Stock, Shares Outstanding		416,746,380
Entity Central Index Key	0001051470
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	FY
Amendment Flag	false
Common Stock, $0.01 par value
Entity Information [Line Items]
Title of 12(b) Security	Common Stock, $0.01 par value
Trading Symbol	CCI
Security Exchange Name	NYSE
6.875% Mandatory Convertible Preferred Stock, Series A, $0.01 par value
Entity Information [Line Items]
Title of 12(b) Security	6.875% Mandatory Convertible Preferred Stock, Series A, $0.01 par value
Trading Symbol	CCI.PRA
Security Exchange Name	NYSE