Commitments and Contingencies (Tables)

12 Months Ended

Dec. 31, 2017

Commitments And Contingencies Disclosure [Abstract]

Future Minimum Annual Rental Commitments under Various Non-cancellable Operating Leases

Rental Commitments

Future minimum annual rental commitments as of December 31, 2017 under various non-cancellable operating leases for our office facilities, which expire at various dates through 2031, are as follows:

Rental Commitments for Years Ended December 31,
amounts in thousands
2018	$	12,075
2019		11,469
2020		11,395
2021		10,315
2022		9,654
2023-2031		36,296
Total Minimum Operating Lease Payments	$	91,204