Commitments and Contingencies

Commitments and Guarantees

Our office lease for our corporate headquarters extends until October 31, 2022. To transport products, we lease tractors, trailers and railcars. In addition, we lease tanks and terminals for the storage of crude oil, petroleum products, NaHS and caustic soda. Additionally, we lease a segment of pipeline where under the terms we make payments based on throughput. We have no minimum volumetric or financial requirements remaining on our pipeline lease.

The future minimum rental payments under all non-cancelable operating leases as of December 31, 2017, were as follows (in thousands):



	Office Space		Transportation Equipment		Terminals and Tanks		Total
2018	$	3,972	$	25,871	$	14,737	$	44,580
2019	3,951		25,209		12,593		41,753
2020	3,984		23,403		8,833		36,220
2021	3,233		17,818		6,545		27,596
2022	2,693		16,317		4,754		23,764
2023 and thereafter	4,696		55,614		55,627		115,937
Total minimum lease obligations	$	22,529	$	164,232	$	103,089	$	289,850

Total operating lease expense from our continuing operations was as follows (in thousands):



Year Ended December 31, 2017	$	36,933
Year Ended December 31, 2016	$	41,906
Year Ended December 31, 2015	$	36,833

We are subject to various environmental laws and regulations. Policies and procedures are in place to monitor compliance and to detect and address any releases of crude oil from our pipelines or other facilities; however no assurance can be made that such environmental releases may not substantially affect our business.

Other Matters

Our facilities and operations may experience damage as a result of an accident or natural disaster. These hazards can cause personal injury or loss of life, severe damage to and destruction of property and equipment, pollution or environmental damage and suspension of operations. We maintain insurance that we consider adequate to cover our operations and properties, in amounts we consider reasonable. Our insurance does not cover every potential risk associated with operating our facilities, including the potential loss of significant revenues. The occurrence of a significant event that is not fully-insured could materially and adversely affect our results of operations. We believe we are adequately insured for public liability and property damage to others and that our coverage is similar to other companies with operations similar to ours. No assurance can be made that we will be able to maintain adequate insurance in the future at premium rates that we consider reasonable.

We are subject to lawsuits in the normal course of business and examination by tax and other regulatory authorities. We do not expect such matters presently pending to have a material effect on our financial position, results of operations or cash flows.