NEW YORK--(BUSINESS WIRE)--Fitch Ratings has upgraded the Issuer Default Ratings (IDRs) of both Pinnacle West Capital Corp. (PNW) and its vertically integrated electric utility subsidiary, Arizona Public Service Co. (APS) by one notch to 'A-' from 'BBB+'. The Rating Outlooks for both PNW and APS are revised to Stable from Positive. Additionally, Fitch has affirmed the short-term IDRs of PNW and APS at 'F2'. A full list of rating actions is detailed at the end of this press release. Approximatel