16. Commitments

Operating Leases At December 31, 2013, the Company had $3.3 billion in long-term drilling rig commitments that satisfy operating lease criteria. The Company also had $388 million of various commitments under non-cancelable operating lease agreements for production platforms and equipment, buildings, facilities, compressors, and aircraft. These operating leases expire at various dates through 2026. Certain of these operating leases contain residual value guarantees at the end of the lease term, totaling $53 million at December 31, 2013. No liability has been accrued for residual value guarantees. In addition, these operating leases include options to purchase the leased property during or at the end of the lease term for the fair market value or other specified amount at that time. The following summarizes future minimum lease payments under operating leases at December 31, 2013:



millions
2014	$	964
2015	948
2016	755
2017	525
2018	309
Later years	189
Total future minimum lease payments	$	3,690

Total rent expense, net of sublease income, amounted to $119 million in 2013, $136 million in 2012, and $143 million in 2011. Total rent expense includes contingent rent expense related to processing fees of $17 million in 2013, $18 million in 2012, and $21 million in 2011.

Drilling Rig Commitments Anadarko has entered into various agreements to secure drilling rigs necessary to execute its drilling plans over the next several years. The table of future minimum lease payments above includes $3.1 billion related to eight offshore drilling vessels and $155 million related to certain contracts for U.S. onshore drilling rigs. Lease payments associated with the drilling of exploratory wells and development wells, net of amounts billed to partners, will initially be capitalized as a component of oil and gas properties, and either depreciated or impaired in future periods or written off as exploration expense.

Spar Platform and Production Vessel Leases Anadarko has operating leases related to certain spar platforms in the Gulf of Mexico. The table of future minimum lease payments above includes approximately $206 million for these agreements.

Other Commitments In the normal course of business, the Company enters into other contractual agreements for processing, treating, transportation, and storage of natural gas, crude oil, and NGLs, as well as for other oil and gas activities. These agreements expire at various dates through 2030. At December 31, 2013, aggregate future payments under these contracts totaled $11.5 billion, of which $2.3 billion is expected to be paid in 2014, $1.8 billion in 2015, $1.4 billion in 2016, $1.2 billion in 2017, $1.1 billion in 2018, and $3.7 billion thereafter.