Financial Instruments and Derivatives - Additional Information (Details) $ / shares in Units, $ in Millions	3 Months Ended
Mar. 31, 2020 USD ($) Contract $ / shares	Dec. 31, 2019 USD ($)
Derivative [Line Items]
Preferred Stock, Redemption Price Per Share \| $ / shares	$ 50.00
Preferred Stock, Redemption Date	Oct. 01, 2026
Designated as Hedging Instrument \| Interest Expense
Derivative [Line Items]
Change in fair value of interest rate derivatives included in AOCI and expected to be reclassified in the next 12 months	$ 1.1
Designated as Hedging Instrument \| Interest Rate Swap [Member]
Derivative [Line Items]
Derivative, Number of Instruments Held \| Contract	0
Fair Value, Measurements, Recurring [Member]
Derivative [Line Items]
Embedded Derivative, Fair Value of Embedded Derivative Asset	$ 8.9	$ 36.5
Fair Value, Measurements, Recurring [Member] \| Other Assets [Member]
Derivative [Line Items]
Interest Rate Derivative Assets, at Fair Value		0.1
Conventional Variable Rate Debt [Member] \| Minimum [Member]
Derivative [Line Items]
Debt Renewal Period	30 days
Conventional Variable Rate Debt [Member] \| Maximum [Member]
Derivative [Line Items]
Debt Renewal Period	90 days
Fixed Rate Debt [Member]
Derivative [Line Items]
Notes Payable Excluding Interest Rate Swaps and Cap Agreements	$ 4,100.0	4,100.0
Notes Payable, Fair Value Disclosure	4,400.0	4,500.0
Floating Rate Debt [Member]
Derivative [Line Items]
Notes Payable Excluding Interest Rate Swaps and Cap Agreements	400.0	400.0
Notes Payable, Fair Value Disclosure	$ 400.0	$ 400.0

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Notes Payable Excluding Interest Rate Swaps and Cap Agreements

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- Definition

The estimated value of gains (losses), net anticipated to be transferred in the future from accumulated other comprehensive income into earnings.

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The number of derivative instruments of a particular group held by the entity.

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Fair value as of the balance sheet date of the embedded derivative or group of embedded derivatives classified as an asset.

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- Definition

Fair value as of the balance sheet date of interest rate derivative assets, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as assets.

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Fair value portion of notes payable.

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Date the preferred stock has been redeemed, in CCYY-MM-DD format.

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The price per share at which the preferred stock of an entity that has priority over common stock in the distribution of dividends and in the event of liquidation of the entity is redeemed or may be called at. The redemption features of this preferred stock are solely within the control of the issuer.

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