After-hours movers:

Netflix (NASDAQ: NFLX) fell 8% after despite better than expected quarterly results, after guidance trailed estimates and Chairman ​Reed Hastings announced his departure.

Alcoa (NYSE: AA) fell 7% after first quarter estimates missed estimates on the top and bottom line. Alcoa reported Q1 EPS of $1.40, $0.07 worse than the analyst estimate of $1.47. Revenue for the quarter came in at $3.19 billion versus the consensus estimate of $3.3 billion.

Knight-Swift Transportation (NYSE: KNX) fell 3% after it cuts Q1 earnings guidance. The revision reflects several factors that affected the quarter's performance, including a large arbitration award.

Trevi Therapeutics Inc. (NASDAQ: TRVI) fell 10% after it announced it has commenced an underwritten public offering of $150 million in common stock shares.

NiSource (NYSE: NI) climbed 3% in after-hours trading Thursday following the announcement of strategic energy infrastructure agreements with subsidiaries of Alphabet Inc. and Amazon Data Services, Inc. to support data center development in Indiana.