Commitments and Contingencies (Tables)

12 Months Ended

Dec. 31, 2018

Commitments and Contingencies Disclosure [Abstract]

Schedule of rent expense associated with operating leases

The table below presents rent expense associated with facility and vehicle operating leases for the past three years (in thousands):

2018		2017		2016
$	70,102	$	66,161	$	63,940

Future minimum lease payments related to non-cancelable operating leases

The table below sets forth the approximate future minimum lease payments as of December 31, 2018 related to non-cancelable facility operating leases with initial terms of one year or more (in thousands):

2019	$	50,416
2020	48,580
2021	37,411
2022	28,078
2023	16,260
Thereafter	16,020