to the heading "Our Business — Challenges and Risks" above and "Item 1A. Risk Factors" in Part I of this report. As a result, management must make numerous assumptions which involve a significant amount of judgment when completing recoverability and impairment tests of noncurrent assets in various regions around the world. 

Investments in Equity and Debt Securities 

The carrying values of our investments in equity securities are determined using the equity method, the cost method or the fair value method. We account for investments in companies that we do not control or account for under the equity method either at fair value or under the cost method, as applicable. Investments in equity securities are carried at fair value, if the fair value of the security is readily determinable. Equity investments carried at fair value are classified as either trading or available-for-sale securities. Realized and unrealized gains and losses on trading securities and realized gains and losses on available-for-sale securities are included in net income. Unrealized gains and losses, net of deferred taxes, on available-for-sale securities are included in our consolidated balance sheets as a component of accumulated other comprehensive income (loss) ("AOCI"). Trading securities are reported as either marketable securities or other assets in our consolidated balance sheets. Securities classified as available-for-sale are reported as either marketable securities or other investments in our consolidated balance sheets, depending on the length of time we intend to hold the investment. Investments in equity securities that do not qualify for fair value accounting are accounted for under the cost method. In accordance with the cost method, our initial investment is recorded at cost and we record dividend income when applicable dividends are declared. Cost method investments are reported as other investments in our consolidated balance sheets. 

Our investments in debt securities are carried at either amortized cost or fair value. Investments in debt securities that the Company has the positive intent and ability to hold to maturity are carried at amortized cost and classified as held-to-maturity. Investments in debt securities that are not classified as held-to-maturity are carried at fair value and classified as either trading or available-for-sale. 

Investments classified as trading securities are not assessed for impairment, since they are carried at fair value with the change in fair value included in net income. We review our investments in equity and debt securities that are accounted for using the equity method or cost method or that are classified as available-for-sale or held-to-maturity each reporting period to determine whether a significant event or change in circumstances has occurred that may have an adverse effect on the fair value of each investment. When such events or changes occur, we evaluate the fair value compared to our cost basis in the investment. We also perform this evaluation every reporting period for each investment for which our cost basis has exceeded the fair value in the prior period. The fair values of most of our Company's