Fair Value of Financial Instruments (Narrative) (Details) $ in Millions	Apr. 23, 2019 USD ($) item	Jun. 30, 2019 USD ($)
Fair Value Of Financial Instruments [Line Items]
Number of Data Centers Acquired | item	2
Acquisition cash consideration	$ 44.0
Senior Notes | Fair Value Measurements, Level 2
Fair Value Of Financial Instruments [Line Items]
Fair value of loan based on current market rates		$ 396.0