Fair value of financial instruments (Tables)

9 Months Ended

Sep. 30, 2019

Fair Value Disclosures [Abstract]

Schedule of Carrying Values and Estimated Fair Values of Debt Instruments

The fair value and carrying value of our fixed-rate debt are as follows:

(In millions)	September 30, 2019		December 31, 2018
Senior unsecured notes
Carrying value	$	600.0	600.0
Fair value	613.0		519.9