Fair Value Measurements and the Fair Value Option - Interest Rate Swaps and Fair Value of Financial Instruments, Narrative (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Reported Value Measurement [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt fair value	$ 4,800.0	$ 5,000.0
Level 2 [Member] | Estimate of Fair Value Measurement [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt fair value	4,900.0	$ 5,200.0
Interest Rate Swap [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative, notional amount	$ 163.4