FAIR VALUE MEASUREMENTS
3 Months Ended
Mar. 31, 2018
Fair Value Disclosures [Abstract]  
FAIR VALUE MEASUREMENTS
FAIR VALUE MEASUREMENTS
 
Our financial assets and liabilities recorded at fair value on a recurring basis primarily relate to investments in available-for-sale securities held by our captive insurance subsidiaries. The following tables present information about our assets and liabilities that are measured at fair value on a recurring basis at March 31, 2018 and December 31, 2017. The following tables also indicate the fair value hierarchy of the valuation techniques we utilized to determine such fair values. In general, fair values determined by Level 1 inputs utilize quoted prices (unadjusted) in active markets for identical assets or liabilities. We consider a security that trades at least weekly to have an active market. Fair values determined by Level 2 inputs utilize data points that are observable, such as quoted prices for similar assets, interest rates and yield curves. Fair values determined by Level 3 inputs are unobservable data points for the asset or liability, and include situations where there is little, if any, market activity for the asset or liability. 
Investments
 
March 31, 2018
 
Quoted Prices
in Active
Markets for
Identical Assets
(Level 1)
 
Significant Other
Observable Inputs
(Level 2)
 
Significant
Unobservable
Inputs
(Level 3)
Marketable equity securities — noncurrent
 
$
34

 
$
34

 
$

 
$

Marketable debt securities — noncurrent
 
22

 
7

 
15

 

 
 
$
56

 
$
41

 
$
15

 
$

 
Investments
 
December 31, 2017
 
Quoted Prices
in Active
Markets for
Identical Assets
(Level 1)
 
Significant Other
Observable Inputs
(Level 2)
 
Significant
Unobservable
Inputs
(Level 3)
Marketable equity securities — noncurrent
 
$
35

 
$
35

 
$

 
$

Marketable debt securities — noncurrent
 
21

 
7

 
14

 

 
 
$
56

 
$
42

 
$
14

 
$


 
Our non-financial assets and liabilities not permitted or required to be measured at fair value on a recurring basis typically relate to long-lived assets held and used, long-lived assets held for sale and goodwill. We are required to provide additional disclosures about fair value measurements as part of our financial statements for each major category of assets and liabilities measured at fair value on a non-recurring basis. The following table presents this information and indicates the fair value hierarchy of the valuation techniques we utilized to determine such fair values. In general, fair values determined by Level 1 inputs utilize quoted prices (unadjusted) in active markets for identical assets or liabilities, which generally are not applicable to non-financial assets and liabilities. Fair values determined by Level 2 inputs utilize data points that are observable, such as definitive sales agreements, appraisals or established market values of comparable assets. Fair values determined by Level 3 inputs are unobservable data points for the asset or liability and include situations where there is little, if any, market activity for the asset or liability, such as internal estimates of future cash flows.
 
 
March 31, 2018
 
Quoted Prices
in Active
Markets for
Identical Assets
(Level 1)
 
Significant Other
Observable Inputs
(Level 2)
 
Significant
Unobservable
Inputs
(Level 3)
Long-lived assets held for sale
 
$
423

 
$

 
$
423

 
$

 
 
$
423

 
$

 
$
423

 
$

 

 
December 31, 2017
 
Quoted Prices
in Active
Markets for
Identical Assets
(Level 1)
 
Significant Other
Observable Inputs
(Level 2)
 
Significant
Unobservable
Inputs
(Level 3)
Long-lived assets held for sale
 
$
456

 
$

 
$
456

 
$

Other than temporarily impaired equity method investments
 
113

 

 
113

 

 
 
$
569

 
$

 
$
569

 
$



As described in Note 5, in the three months ended March 31, 2018, we recorded $19 million of impairment charges, consisting primarily of $17 million of charges to write-down assets held for sale to their estimated fair value, less estimated costs to sell, for certain of our Chicago-area facilities.

The fair value of our long-term debt (except for borrowings under the Credit Agreement) is based on quoted market prices (Level 1). The inputs used to establish the fair value of the borrowings outstanding under the Credit Agreement are considered to be Level 2 inputs, which include inputs other than quoted prices included in Level 1 that are observable, either directly or indirectly. At both March 31, 2018 and December 31, 2017, the estimated fair value of our long-term debt was approximately 100.2% of the carrying value of the debt.