Fair Value Measurements

3 Months Ended

Mar. 31, 2016

The following fair value hierarchy table categorizes information regarding our net financial assets measured at fair value on a recurring basis (in millions):



	Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)			Significant Unobservable Inputs (Level 3)		Total
As of March 31, 2016
Supplemental executive retirement plan assets	$	32.7	$	—		$	—	$	32.7
Derivatives, net	—		0.1			—		0.1
Total financial assets	$	32.7	$	0.1		$	—	$	32.8

As of December 31, 2015
Supplemental executive retirement plan assets	$	33.1	$	—		$	—	$	33.1
Total financial assets	$	33.1	$	—		$	—	$	33.1
Derivatives, net	—		(19.7		)	—		(19.7		)
Total financial liabilities	$	—	$	(19.7	)	$	—	$	(19.7	)

Supplemental Executive Retirement Plan Assets

Our supplemental executive retirement plans (the "SERP") are non-qualified plans that provide eligible employees an opportunity to defer a portion of their compensation for use after retirement. Assets held in the SERP were marketable securities measured at fair value on a recurring basis using Level 1 inputs and were included in other assets, net, on our condensed consolidated balance sheets. The fair value measurement of assets held in the SERP was based on quoted market prices.

Derivatives

Our derivatives were measured at fair value on a recurring basis using Level 2 inputs. See "Note 3 - Derivative Instruments" for additional information on our derivatives, including a description of our foreign currency hedging activities and related methodologies used to manage foreign currency exchange rate risk. The fair value measurement of our derivatives was based on market prices that are generally observable for similar assets or liabilities at commonly-quoted intervals.

Other Financial Instruments

The carrying values and estimated fair values of our debt instruments were as follows (in millions):



	March 31, 2016				December 31, 2015
	Carrying Value		Estimated Fair Value		Carrying Value		Estimated Fair Value
4.70% Senior notes due 2021	$	1,477.8	$	1,048.1	$	1,476.7	$	1,254.0
5.75% Senior notes due 2044	993.7		514.6		993.5		707.1
6.875% Senior notes due 2020	986.5		663.8		990.9		850.5
5.20% Senior notes due 2025	692.7		389.4		692.5		505.2
4.50% Senior notes due 2024	619.9		349.7		619.7		417.4
8.50% Senior notes due 2019	561.9		441.8		566.4		510.2
7.875% Senior notes due 2040	379.4		161.6		379.8		244.0
7.20% Debentures due 2027	149.1		79.5		149.1		133.5
Total	$	5,861.0	$	3,648.5	$	5,868.6	$	4,621.9

The estimated fair values of our senior notes and debentures were determined using quoted market prices. The estimated fair values of our cash and cash equivalents, short-term investments, receivables, trade payables and other liabilities approximated their carrying values as of March 31, 2016 and December 31, 2015.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

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