Leases

We lease office space and equipment under operating lease agreements with varying terms. Certain leases require us to pay property taxes, insurance and routine maintenance and include renewal options and escalation clauses. Rent expense was $46 million, $45 million and $47 million in 2017, 2016 and 2015, respectively. Future minimum lease payments under non-cancelable operating leases at December 31, 2017 were as follows:



Years ending December 31,
2018	$	47,820
2019	39,107
2020	30,180
2021	22,266
2022	15,256
Thereafter	63,685
Total minimum lease payments	$	218,314