Leases

We lease some of our office space under non-cancelable operating leases with third parties and sublease office space to third parties. Some of our lease agreements contain renewal options and escalation clauses based on increases in property taxes and building operating costs.

As of December 31, 2016, future minimum lease payments under non-cancelable operating leases (net of sublease income) are as follows:



	Gross Lease Commitments		Sublease Income		Net Lease Commitments
	(in millions)
Year ending December 31:
2017	$	76	$	3	$	73
2018	73		3		70
2019	67		3		64
2020	57		3		54
2021	46		3		43
Thereafter	113		5		108
Total future minimum lease payments	$	432	$	20	$	412

Rent expense for operating leases (net of sublease income of $4 million in 2016, $5 million in 2015 and $4 million in 2014) was $78 million in 2016, $88 million in 2015 and $93 million in 2014.