FAIR VALUE

Fair value focuses on the estimated price that would be received to sell an asset or paid to transfer a liability, which is referred to as the exit price. Inputs to valuation techniques used to measure fair value fall into three broad levels (Levels 1, 2, and 3) as follows:

Level 1—Observable inputs that reflect quoted prices for identical assets or liabilities in active markets that we have the ability to access at the measurement date.

Level 2—Observable inputs, other than quoted prices included in Level 1, for the asset or liability or prices for similar assets and liabilities.

Level 3—Unobservable inputs reflecting the reporting entity’s estimates of the assumptions that market participants would use in pricing the asset or liability (including assumptions about risk).

All marketable securities were valued based on quoted prices for similar assets in active markets or quoted prices for identical or similar assets in markets that are not active (Level 2 in the fair value hierarchy). We measure our marketable securities on a recurring, monthly basis. See Note 4, Marketable Securities, for information on the fair value of our marketable securities.

In connection with the June 1, 2016 acquisition of WSL, a contingent payment arrangement based on the achievement of specified earnings targets is in place for three consecutive 12-month periods after the closing, with the aggregate payment total not to exceed $40.0 million. No payments have been made through March 31, 2018. The fair value of the contingent consideration at March 31, 2018 and December 31, 2017 was zero. The valuation was based on Level 3 inputs.

There were no transfers between levels for the periods shown.

Fair Value of Other Financial Instruments

The recorded value of cash, trade accounts receivable, and trade accounts payable approximates fair value.

The table below presents the carrying value of our debt portfolio along with the fair value of a fixed-rate debt portfolio with similar terms and maturities, which is based on borrowing rates available to us in the applicable year. This valuation used Level 2 inputs.

March 31, 2018

December 31, 2017

(in millions)

Carrying Value

Fair Value

Carrying Value

Fair Value

Debt portfolio

423.8

418.1

429.8

432.4