Subsequent Events (Narrative) (Details) (USD $)						0 Months Ended
	Sep. 30, 2014 Credit Facility [Member]	Jun. 30, 2014 Credit Facility [Member]	Sep. 30, 2014 Accordion [Member] Credit Facility [Member] Plan [Member]	Oct. 30, 2014 Subsequent Event [Member] Credit Facility [Member]	Oct. 30, 2014 Subsequent Event [Member] Accordion [Member] Credit Facility [Member]	Oct. 01, 2014 Subsequent Event [Member] WesTower [Member]	Oct. 01, 2014 Subsequent Event [Member] WesTower [Member]
Subsequent Events [Line Items]
Business combinations, percentage of voting interests acquired							100.00%
Business combinations, payments in cash						$ 199,000,000
Line of credit facility, maximum borrowing capacity	1,000,000,000	750,000,000	250,000,000	1,075,000,000.000
Line of credit facility, term loan					$ 75,000,000