Supplemental Cash Flow Information (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Cash paid for:
Interest	$ 22.0	$ 22.0
Income taxes	4.0	6.0
Non-cash investing and financing activities:
Change in proceeds of sales of investments available for sale receivable in period	0.0	(44.0)
Change in purchases of investments available for sale payable in period	0.0	20.0
Change in treasury stock purchases payable in period	5.0	0.0
Lease liabilities recognized in exchange for lease right-of-use assets	8.0	6.0
Remeasurement of lease liabilities	$ 22.0	$ 9.0

Lessee, Operating Lease, Remeasurement Of Lease Liability

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Noncash Investing and Financing Activities, Change in Treasury Stock Purchases Payable

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Noncash Investing and Financing Activities, Change in Proceeds of Sales of Investments

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Noncash Investing and Financing Activities, Change in Purchases of Investments

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- Definition

The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes.

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Amount of increase in right-of-use asset obtained in exchange for operating lease liability.

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