Condensed Consolidated Statements of Cash Flows (USD $)
In Millions, unless otherwise specified
3 Months Ended
Mar. 31, 2015
Mar. 31, 2014
CASH FLOWS FROM OPERATING ACTIVITIES:    
Net (loss) income $ (4.9) $ 0.4
Adjustments to reconcile net income (loss) to net cash provided by operating activities:    
Depreciation and amortization expense 67.3 57.6
Amortization of aerial image library, deferred contract costs and lease incentive 4.5 5.0
Non-cash stock-based compensation expense, net of capitalized stock-based compensation expense 4.6 3.9
Amortization of debt issuance costs and accretion of debt discount, net of capitalized interest 1.7  
Deferred income taxes (5.9) 3.8
Excess tax benefit from share-based compensation (0.9)  
Other 0.4 1.2
Changes in working capital, net of assets acquired and liabilities assumed in business combinations:    
Accounts receivable, net 3.6 0.1
Deferred contract costs (4.8) (0.4)
Other current and non-current assets 4.8 6.7
Accounts payable 5.8 (12.1)
Accrued liabilities 0.5 (12.7)
Deferred revenue (19.8) (13.6)
Net cash flows provided by operating activities 56.9 39.9
CASH FLOWS FROM INVESTING ACTIVITIES:    
Construction in progress additions (30.1) (61.8)
Property and equipment additions (1.2) (2.2)
Acquisition of businesses, net of cash acquired   (35.7)
Decrease in restricted cash   2.0
Net cash flows used in investing activities (31.3) (97.7)
CASH FLOWS FROM FINANCING ACTIVITIES:    
Repayment of debt (1.4) (1.4)
Principal payments on capital lease obligations (0.2) (0.2)
Repurchase of common stock (31.1)  
Proceeds from exercise of stock options 4.3 1.8
Preferred stock dividend payment (1.0) (1.0)
Excess tax benefit from share-based compensation 0.9  
Net cash flows used in financing activities (28.5) (0.8)
Net decrease in cash and cash equivalents (2.9) (58.6)
Cash and cash equivalents, beginning of period 117.8 229.1
Cash and cash equivalents, end of period 114.9 170.5
SUPPLEMENTAL CASH FLOW INFORMATION:    
Cash paid for interest, net of capitalized amounts of $11.5 million and $21.1 million, respectively 9.6  
NON-CASH INVESTING AND FINANCING ACTIVITIES:    
Changes to non-cash property, equipment and construction in progress accruals, including interest 3.2 12.0
Non-cash preferred stock dividend accrual $ (1.0) $ (1.0)