Issue link: http://catalog.e-digitaleditions.com/i/275023
28 Dollar amounts in millions except per share amounts or as otherwise specified The following is a rollforward of our assets and liabilities measured at fair value using unobservable inputs (Level 3): Total Corporate and Asset- Backed Debt Securities Contingent Consideration 2013 2012 2013 2012 2013 2012 Balance at the beginning of the period $ (103) $ (114) $ — $ 1 $ (103) $ (115) Transfers into Level 3 — — — — — — Transfers out of Level 3 — — — — — — Gains or (losses) included in earnings 5 6 — — 5 6 Sales — (1) — (1) — — Settlements 39 39 — — 39 39 Other — (33) — — — (33) Balance at the end of the period $ (59) $ (103) $ — $ — $ (59) $ (103) The estimated fair value of the liability for contingent consideration represents milestone payments for acquisitions. The fair value of the liability was estimated using a discounted cash flow technique. Significant inputs to this technique included our probability assessments of occurrence of triggering events, appropriately discounted considering the uncertainties associated with the obligation. We remeasure this liability each reporting period and record the changes in the fair value in general and administrative expense (for probability of occurrence) and other income (expense) (for changes in time value of money) in earnings. The following presents quantitative information about the inputs and valuation methodologies we use for material fair value measurements classified in Level 3: Probability Range (Weighted Average) Fair Value Valuation Technique Unobservable Input Minimum Maximum Weighted Average Contingent consideration $59 Discounted cash flow Probability of occurrence 85 100 95 The following is a summary of our marketable securities: Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value 2013 2012 2013 2012 2013 2012 2013 2012 Available-for-sale marketable securities: Corporate and asset-backed debt securities $ 1,177 $ 1,277 $ 1 $ 4 $ (1) $ (1) $ 1,177 $ 1,280 Foreign government debt securities 846 846 — 2 (1) — 845 848 United States agency debt securities 211 288 — — — — 211 288 United States treasury debt securities 350 343 — — — — 350 343 Certificates of deposit 53 114 — — — — 53 114 Other 5 17 — — — — 5 17 Total available-for-sale marketable securities $ 2,642 $ 2,885 $ 1 $ 6 $ (2) $ (1) 2,641 2,890 Trading marketable securities 72 57 Total marketable securities $ 2,713 $ 2,947 Reported as: Current assets-marketable securities $ 2,641 $ 2,890 Noncurrent assets-other 72 57 $ 2,713 $ 2,947 The unrealized losses on our available-for-sale marketable securities were primarily caused by increases in yields as a result of changing conditions in the global credit markets. While some of these investments have been downgraded by rating agencies since their initial purchase, less than 1% of our investments in available-for-sale marketable securities had a credit quality rating of less than single A (per Standard & Poors and Fitch) and A2 (per Moody's). Because we do not intend to sell the investments and it is not more likely than not that we will be required to sell the investments before recovery of their amortized cost basis, which may be maturity, we do not consider these investments to be other-than-temporarily impaired at December 31, 2013. The cost and estimated fair value of available-for-sale marketable securities at December 31, 2013 by contractual maturity are: Cost Estimated Fair Value Due in one year or less $ 425 $ 424 Due after one year through three years 1,989 1,989 Due after three years 228 228 $ 2,642 $ 2,641