We have categorized our cash equivalents held in money market funds and our investments held at fair value into a three-level fair value hierarchy based on the priority of the inputs to the valuation technique for the cash equivalents and  investments as follows: Level 1 - Values based on unadjusted quoted prices for identical assets or liabilities in an active market; Level 2 - Values based on quoted prices in markets that are not active or model inputs that are observable either directly or indirectly; Level 3 - Values based on prices or valuation techniques that require inputs that are both unobservable  and significant to the overall fair value measurement. These inputs include information supplied by investees. Fair Value Measurements at December 31, 2012 Using ADTRAN 2013 Annual Report 54 (In thousands)  Fair Value Quoted Prices  in Active  Markets for Identical  Assets (Level 1) Significant Other  Observable  Inputs  (Level 2) Significant  Unobservable  Inputs  (Level 3) Cash equivalents Money market funds $28,071 $28,071  $— $— Available-for-sale securities Deferred compensation plan assets 11,527 11,527  —   —  Available-for-sale debt securities Corporate bonds 186,412 — 186,412 — Municipal fixed-rate bonds 175,084 — 175,084  — Municipal variable rate demand notes 34,375 — 34,375 — Fixed income bond fund 456 456 — — Available-for-sale marketable equity securities Marketable equity securities— technology industry 14,099 14,099  —   —  Marketable equity securities—other 21,105 21,105 — — Available-for-sale securities 443,058 47,187 395,871  — Total  $471,129 $75,258 $395,871 $— (In thousands)  Fair Value Quoted Prices  in Active  Markets for Identical  Assets (Level 1) Significant Other  Observable  Inputs  (Level 2) Significant  Unobservable  Inputs  (Level 3) Cash equivalents Money market funds $3,949 $3,949  $— $— Available-for-sale securities Deferred compensation plan assets 15,123 15,123  —   —  Available-for-sale debt securities Corporate bonds 166,859 — 166,859 — Municipal fixed-rate bonds 136,302 — 136,302  — Municipal variable rate demand notes 8,310 — 8,310 — Available-for-sale marketable equity securities Marketable equity securities— technology industry 11,398 11,398  —   —  Marketable equity securities—other 27,054 27,054 — — Available-for-sale securities 365,046 53,575 311,471  — Total  $368,995 $57,524 $311,471 $— Fair Value Measurements at December 31, 2013 Using