The pilots of Delta Air Lines approved a new four-year contract that protects their prized profit-sharing arrangement and buoys the group back to a position among the industry's top-paid.

Nearly all of Delta's pilots cast a vote, with 82 percent of them choosing ratification when the ballots were counted Thursday — the highest approval rate of a pilot contract involving the Atlanta-based airline.

The contract gives a 30 percent raise over four years to the pilots, with the biggest increase of 18 percent applied retroactively to Jan. 1, 2016. The pilots will receive a 3 percent raise in 2017 and again in 2018 and a 4 percent raise in 2019.

The vote eases relations that were at times tense between airline management and the pilots as well as within the pilots' group. Ratification comes 18 months after the pilots rejected a divisive agreement management made with the union's previous leadership.

With new union representatives, and emboldened by Delta's record profit last year of $4.5 billion, the group rallied around a message of fairness.

The 13,000 Delta pilots, represented by the Air Line Pilots Association International, have been fighting to regain wage concessions given up during the airline's bankruptcy a decade ago.

Tim Canoll, president of the pilots' group, said the organization is committed to seeing all of its members "share in their companies' success, particularly when those airlines are experiencing record profits."

The pilots are Delta's only unionized employees.

Last year, the company trimmed the profit-sharing for the rest of its working groups, including flight attendants and ground crew, but increased their base pay by 18.5 percent. Another 6 percent increase is slated for next April.