NEW YORK--(BUSINESS WIRE)--SL Green Realty Corp (NYSE:SLG), an S&P 500 company and New York City’s largest commercial landlord, today announced that it has expanded its unsecured corporate credit facility by $500 million, to $2.533 billion. The revolving line of credit portion of the facility, which matures in March 2020, has been increased by $400 million to $1.6 billion and the term loan portion of the facility, which matures in June 2019, has been increased by $100 million to $933 millio