Debt and Credit Arrangements (Tables)

6 Months Ended

Jun. 30, 2018

Debt Disclosure [Abstract]

Summary of Carrying Amounts and Fair Values of Long-term Debt

A summary of the carrying amounts and fair values of our long-term debt is listed below.

	Effective Interest Rate	June 30, 2018				December 31, 2017
		Book Value		Fair Value 1		Book Value		Fair Value 1
4.00% Senior Notes due 2022 (less unamortized discount and issuance costs of $1.2 and $0.9, respectively)	4.13%	$	247.9	$	251.6	$	247.6	$	259.0
3.75% Senior Notes due 2023 (less unamortized discount and issuance costs of $0.7 and $1.9, respectively)	4.32%	497.4		495.6		497.1		513.2
4.20% Senior Notes due 2024 (less unamortized discount and issuance costs of $0.6 and $2.4, respectively)	4.24%	497.0		503.3		496.7		524.2
Other notes payable and capitalized leases		40.5		40.5		46.2		46.2
Total long-term debt		1,282.8				1,287.6
Less: current portion		0.1				2.0
Long-term debt, excluding current portion		$	1,282.7			$	1,285.6

1 See Note 13 for information on the fair value measurement of our long-term debt.