The table below summarizes the carrying amount and fair value of the Company’s publicly traded debt and non-publicly traded debt in accordance with the Fair Value Measurements and Disclosures Topic of the ASC. The fair values of the Company’s publicly traded debt are based on quoted market prices. The fair values of the Company’s non-publicly traded debt are estimated using discounted cash flow analyses, based on the Company’s current incremental borrowing rates for similar types of borrowing arrangements. The Company’s publicly traded debt and non-publicly traded debt are classified as level 1 and level 2, respectively, in the fair value hierarchy.



(Thousands of dollars)
	March 31, 2018				March 31, 2017
	Carrying Amount		Fair Value		Carrying Amount		Fair Value
Publicly traded debt	$	8,739,950	$	8,670,864	$	1,908,209	$	1,925,031
Non-publicly traded debt	1,152,246		1,082,658		4,089		3,770