Note 15. Commitments and Contingencies

Lease Commitments

We lease land, buildings, equipment and vehicles under non‑cancelable operating leases expiring in various years through 2041. Rent expense for leases that contain scheduled rent increases are recorded on a straight‑line basis. Several of the leases have renewal options providing for additional lease periods. Future minimum payments, by year and in the aggregate, under the non‑cancelable leases with initial or remaining terms of one year or more, consisted of the following as of December 31, 2018:


	Operating
	Leases
	(in millions)
2019	$	59.5
2020		45.5
2021		32.9
2022		22.7
2023		16.2
Thereafter		40.7
	$	217.5

Total rental expense amounted to $82.7 million, $77.9 million and $78.9 million in 2018, 2017 and 2016, respectively.

Included in the amounts for operating leases are lease payments to various related parties, who are not executive officers of the Company, in the amounts of $4.1 million, $3.4 million and $3.6 million in 2018, 2017 and 2016, respectively. These related party leases are for buildings leased to certain of the companies we have acquired and expire in various years through 2023.

Purchase Commitments

As of December 31, 2018, we had commitments to purchase minimum quantities of certain metal products, which we entered into to secure material for corresponding long‑term sales commitments we have entered into with our customers. The total amount of the minimum commitments based on current pricing is estimated at approximately $149.9 million, with amounts in 2019, 2020 and thereafter being $90.7 million, $28.6 million and $30.6 million, respectively.

Collective Bargaining Agreements

As of December 31, 2018, approximately 11%, or 1,780, of our total employees are covered by 40 collective bargaining agreements at 51 of our different locations, which expire at various times over the next seven years. Approximately 400 of our employees are covered by 13 different collective bargaining agreements that will expire during 2019.

Environmental Contingencies

We are subject to extensive and changing federal, state, local and foreign laws and regulations designed to protect the environment, including those relating to the use, handling, storage, discharge and disposal of hazardous substances and the remediation of environmental contamination. Our operations use minimal amounts of such substances.

We believe we are in material compliance with environmental laws and regulations; however, we are from time to time involved in administrative and judicial proceedings and inquiries relating to environmental matters. Some of our owned or leased properties are located in industrial areas with histories of heavy industrial use. We may incur some environmental liabilities because of the location of these properties. In addition, we are currently involved with an environmental remediation project related to activities at former manufacturing operations of EMJ, our wholly owned subsidiary, that were sold many years prior to our acquisition of EMJ in 2006. Although the potential cleanup costs could be significant, EMJ maintained insurance policies during the time it owned the manufacturing operations that have covered costs incurred to date, and are expected to continue to cover the majority of the related costs. We do not expect that this obligation will have a material adverse impact on our consolidated financial position, results of operations or cash flows.

Legal Matters

From time to time, we are named as a defendant in legal actions. Generally, these actions arise in the ordinary course of business. We are not currently a party to any pending legal proceedings other than routine litigation incidental to the business. We expect that these matters will be resolved without having a material adverse effect on our results of operations, financial condition or cash flows. We maintain general liability insurance against risks arising in the ordinary course of business.