Leases

We have noncancelable operating leases for office and plant facilities, equipment and automobiles that expire at various dates through 2040. Certain operating leases have renewal options and rent escalation clauses as well as various purchase options.

Lease right-of-use assets represent the right to use an underlying asset pursuant to the lease for the lease term, and lease liabilities represent the obligation to make lease payments arising from the lease. Lease right-of-use assets and lease liabilities are recognized at the commencement of an arrangement where it is determined at inception that a lease exists. These assets and liabilities are initially recognized based on the present value of lease payments over the lease term calculated using our incremental borrowing rate generally applicable to the location of the lease right-of-use asset, unless an implicit rate is readily determinable. We combine lease and certain non-lease components in determining the lease payments subject to the initial present value calculation. Lease right-of-use assets include upfront lease payments and exclude lease incentives, where applicable. Lease terms include options to extend or terminate the lease when it is reasonably certain that those options will be exercised.

Lease expense for operating leases consists of both fixed and variable components. Expense related to fixed lease payments are recognized on a straight-line basis over the lease term. Variable lease payments are generally expensed as incurred, where applicable, and include certain index-based changes in rent, certain non-lease components, such as maintenance and other services provided by the lessor, and other charges included in the lease. Leases with an initial term of twelve months or less are not recorded on the balance sheet. The depreciable life of lease right-of-use assets is generally the expected lease term, unless there is a transfer of title or purchase option reasonably certain of exercise for such assets.

We recognized total lease expense of $16.5 million for the three months ended March 31, 2019 primarily related to operating lease costs paid to lessors from operating cash flows. We did not recognize any new significant leases in our Condensed Consolidated Balance Sheet for the quarter ended March 31, 2019.

The aggregate annual maturities of operating lease liabilities are as follows (dollars in thousands):



Nine months ended December 31, 2019	$	32,434
2020	38,124
2021	31,297
2022	24,010
2023	20,164
Thereafter	58,097
Total lease payments	204,126
Less imputed interest	(36,026		)
Total	$	168,100

Operating lease right-of-use assets as of March 31, 2019 were recorded in our Condensed Consolidated Balance Sheets as other assets, net of $160.2 million. Operating lease liabilities of $168.1 million as of March 31, 2019 were recorded in our Condensed Consolidated Balance Sheets as accrued liabilities of $33.7 million and other liabilities of $134.4 million. At March 31, 2019, our operating leases had a weighted average discount rate of 5.8 percent and a weighted average remaining lease term of approximately six years.

To a lesser extent, we have certain leases that qualify as finance leases. Finance lease right-of-use assets as of March 31, 2019 were recorded in our Condensed Consolidated Balance Sheets as property, plant and equipment, net of $22.6 million. Finance lease liabilities of $22.2 million as of March 31, 2019 were recorded in our Condensed Consolidated Balance Sheets as revolving loans and current portion of long term-debt of $1.1 million and long-term debt of $21.1 million.

At March 31, 2019, we did not have any significant operating or finance leases that had not commenced.