Commitments

The annual future minimum lease payments for heavy equipment, office equipment and premises in respect of operating leases, excluding contingent rentals, for the next five years and thereafter are as follows:



For the year ending December 31,
2016	$	3,982
2017	3,882
2018	4,041
2019	3,740
2020 and thereafter	11,437
	$	27,082

Total contingent rentals on operating leases consisting principally of usage (recovery) charges in excess of minimum contracted amounts for the years ended December 31, 2015, 2014 and 2013 amounted to $524, $2,116, and $(249) respectively.