Non-Mineral Leases (Tables)

12 Months Ended

Dec. 31, 2011

Future Minimum Rental Payments Due under Noncancelable Leases

At December 31, 2011, future minimum rental payments due under noncancelable leases related to continuing and discontinued operations were:

	Millions of Dollars
2012	$	767
2013		519
2014		382
2015		300
2016		202
Remaining years		591
Total		2,761
Less income from subleases		132	*
Net minimum operating lease payments	$	2,629

* Includes $64 million related to subleases to related parties.

Operating Leases Rental Expense

Operating lease rental expense included in continuing operations for the years ended December 31 was:

	Millions of Dollars
	2011			2010			2009
Total rentals*	$	304			267			259
Less sublease rentals		(14	)		(14	)		(18	)
	$	290			253			241

* Includes $29 million, $16 million and $15 million of contingent rentals in 2011, 2010 and 2009, respectively. Contingent rentals primarily are related to drilling equipment and are based on usage or volume of product sold.