Significant Accounting Policies Investments (Policies)	12 Months Ended
Significant Accounting Policies Investments (Policies)	Dec. 31, 2018
Accounting Policies [Abstract]
Investments	Investments Our non-publicly traded investments and all other publicly traded investments are accounted for using the equity method or are recorded at fair value. We regularly review our investments to determine whether a significant event or change in circumstances has occurred that may impact the fair value of each investment, with changes to fair value recorded in earnings. We evaluate fair value based on specific information (valuation methodologies, estimates of appraisals, financial statements, etc.) in addition to quoted market price, if available. We consider all known quantitative and qualitative factors in determining if a decline in value of an investment has occurred.

Disclosure of accounting policy for investments in financial assets, including marketable securities (debt and equity securities with readily determinable fair values), investments accounted for under the equity method and cost method, securities borrowed and loaned, and repurchase and resale agreements. For marketable securities, the disclosure may include the entity's accounting treatment for transfers between investment categories and how the fair values for such securities are determined. Also, for all investments, an entity may describe its policy for assessing, recognizing and measuring impairment of the investment.