Fair value of financial instruments (Tables)

6 Months Ended

Jun. 30, 2016

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)	June 30, 2016		December 31, 2015
Unsecured notes issued in a private placement
Carrying value	$	85.7	92.9
Fair value	90.1		95.7