Refer to the article "rising interest rates trigger losses on banks massive bond holdings" in wall street journal (december 7, 2016).  what is the difference between realized and unrealized gains and losses on security holdings?  what are the three categories of investments identified in authoritative accounting literature? cite the authoritative guidance you are referencing.  what is the difference in accounting treatment of unrealized gains and losses across these three categories of investments? cite the authoritative guidance you are referencing.  why do unrealized losses affect a bank's book value but "don't immediately diminish a banks profits"? in your answer, define the "special 'accumulated other comprehensive income.'"