Fair Value Measurements	9 Months Ended
Fair Value Measurements	Sep. 30, 2020
Fair Value Disclosures [Abstract]
Fair Value Disclosures [Text Block]	NOTE 4. FAIR VALUE MEASUREMENTS Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. The fair value hierarchy requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. We are required to classify these financial assets and liabilities into two groups: (i) recurring—measured on a periodic basis and (ii) non-recurring—measured on an as-needed basis. During the nine months ended September 30, 2020, we sold our auction rate securities (ARS) and recognized a $3 million gain on available for sale securities, which is included in investment income in the Condensed Consolidated Statements of Income. Available for sale securities were $5 million as of December 31, 2019. Trading securities consist of rabbi trust financial assets, which are recorded in other assets in our Condensed Consolidated Balance Sheets. The assets of the rabbi trust are invested in mutual funds and are reported at fair value based on active market quotations, which represent Level 1 inputs. The assets of the rabbi trust were $4 million at September 30, 2020, and December 31, 2019. We estimated our 4.875% Senior Notes due in 2024 (2024 Senior Notes) to have a fair value of $360 million as of September 30, 2020, based upon market quotations. Our 2024 Senior Notes and other long-term debt are categorized as Level 1 in the U.S. GAAP fair value hierarchy. Fair values are based on trading activity among the Company’s lenders and the average bid and ask price as determined using published rates. There were no outstanding amounts borrowed under our Amended Credit Facility as of September 30, 2020. Carrying amounts reported on the balance sheet for cash and cash equivalents, accounts receivables, and accounts payable approximate fair value due to the short-term maturity of these items. During the three and nine months ended September 30, 2020, and 2019, no adjustments were recognized associated with the fair value of these assets.

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.