Acquisitions (Details) (USD $)	3 Months Ended	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2012		Sep. 30, 2011	Jun. 30, 2012
Business Acquisition [Line Items]
Share-based Compensation		$ 33,573,000		$ 24,937,000
Net revenues		1,793,787,000		1,600,528,000
Current assets	73,851,000	73,851,000			74,246,000
Property and equipment	520,361,000	520,361,000			515,984,000
Goodwill	697,448,000	697,448,000			682,148,000
Other intangible assets, net	195,000,000	195,000,000			195,000,000
Current liabilities	(104,083,000)	(104,083,000)			(86,433,000)
Below-market tenant leases and other non-current liabilities	(337,806,000)	(337,806,000)			(330,045,000)
Deferred income tax liabilities	(51,304,000)	(51,304,000)			(57,433,000)
Net assets acquired	997,718,000	997,718,000			997,718,000
Business acquisition, purchase price allocation, non-current assets, prepaid rent	4,251,000	4,251,000			4,251,000
Average amortization period, long-term prepaid rent	20 years	22 years 10 months 24 days
Net income (loss)		190,451,000	[1]	97,899,000
Basic net income (loss) attributable to CCIC common stockholders, after deduction of dividends on preferred stock, per common share		$ 0.64		$ 0.28
Diluted net income (loss) attributable to CCIC common stockholders, after deduction of dividends on preferred stock, per common share				$ 0.28
Wireless Capital Partners, LLC [Member]
Business Acquisition [Line Items]
Goodwill	54,800,000	54,800,000
Ground lease related assets	2,300	2,300
Business acquisition, purchase price allocation, non-current liabilities, long-term debt assumed	336,300,000	336,300,000
Business acquisition, cost of acquired entity, purchase price	214,700,000	214,700,000
NextG Networks Inc. [Member]
Business Acquisition [Line Items]
Share-based Compensation				46,300,000
Severance Costs		4,200,000
Goodwill	697,400,000	697,400,000
Business acquisition, cost of acquired entity, cash paid	1,000,000,000	1,000,000,000
Business acquisition, cost of acquired entity, purchase price	1,000,000,000	1,000,000,000
Percentage of Total Nodes	75.00%	75.00%
Other incremental acquisition costs		4,700,000
Business Combination, Integration Related Costs				15,700,000
Other Intangible Assets [Member]
Business Acquisition [Line Items]
Average amortization period, long-term prepaid rent	0 years	18 years 9 months 18 days
Site Rental Contracts and Customer Relationships [Member]
Business Acquisition [Line Items]
Average amortization period, long-term prepaid rent	20 years	23 years 3 months 18 days
Long-term prepaid rent [Member] | Wireless Capital Partners, LLC [Member]
Business Acquisition [Line Items]
Business acquisition, purchase price allocation, non-current assets, prepaid rent	322,400,000	322,400,000
Average amortization period, long-term prepaid rent		38 years
Pro forma adjustment for reclassification of valuation allowance [Member]
Business Acquisition [Line Items]
Business acquisition, pro forma adjustment		11,700,000		(50,400,000)
Restricted cash, current and non-current [Member] | Wireless Capital Partners, LLC [Member]
Business Acquisition [Line Items]
Business acquisitions, purchase price allocation, current assets, restricted cash	$ 39,200,000	$ 39,200,000

[1] Inclusive of $46.3 million in NextG stock-based compensation charges and $15.7 million in acquisition and integration costs incurred by NextG.