Aggregate dividends declared during the period for each share of common stock outstanding.

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Contractual interest rate for funds borrowed, under the debt agreement.

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The cash outflow for the extinguishment of long-term borrowing, with the highest claim on the assets of the entity in case of bankruptcy or liquidation, before its maturity.

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Subsequent Events (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended
	Feb. 24, 2020	Jan. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
5.750% notes, issued in June 2010 and due in January 2021 \| Notes payable
Subsequent events
Stated interest rate (as a percent)			5.75%	5.75%
Subsequent event
Subsequent events
Common stock, dividends declared (in dollars per share)	$ 0.2325	$ 0.2325
Subsequent event \| 5.750% notes, issued in June 2010 and due in January 2021 \| Notes payable
Subsequent events
Early repayment of notes payable		$ 250.0
Stated interest rate (as a percent)		5.75%