ChrisBoswell/iStock via Getty ImagesAvista Corporation (NYSE:AVA) is a holding company for two regulated utilities: Avista Utilities and Alaska Electric Light & Power (AEL&P). It is headquartered in Spokane, Washington. Avista Utilities has 377,000 gas customers and 411,000 electric customers concentrated in eastern Washington state, northwestern Idaho and northern and central Oregon. Alaska Electric Light & Power is a purely electric company serving 17,000 customers in the City of Juneau. Avista has a  ...