In addition to exploration and production, the company engaged in petroleum and natural gas gathering, processing, treating, and transportation. The company also participated in the hard minerals business through its ownership of non-operated joint ventures and royalty arrangements. As of December 31, 2018, the company had approximately 1.473 billion barrels of oil equivalent (9.01×109 GJ) of proved reserves, 45% of which was oil reserves, 37% of which was natural gas, and 18% was natural gas liquids.