After a dozen years leading Covington & Burling, Timothy Hester is stepping down as the firm’s chairman at the end of 2019 and turning the role over to a successor, Douglas Gibson, a top corporate partner whose client roster includes major professional sports leagues.

For Covington, the transition caps a decadelong era of international expansion and revenue growth under Hester, 64, an antitrust partner who was first named chairman in 2008 at the height of the financial crisis. The firm avoided layoffs amid the recession and has since doubled in size, opening eight new offices as annual revenue grew from $500 million to more than $1 billion.