Commitments and Contingencies (Tables)

12 Months Ended

Dec. 31, 2018

Commitments and Contingencies Disclosure [Abstract]

Future Minimum Rental Commitments under Office and Equipment Leases

Future minimum rental commitments under such office and equipment leases as of December 31, 2018 are as follows:

(Expressed in thousands)
2019	$	39,684
2020	36,851
2021	32,858
2022	29,604
2023	27,356
2024 and thereafter	114,256
	$	280,609