Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

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Gain (loss) related to the termination of a contract between the parties. The termination may be due to many causes including early termination of a lease by a lessee, a breach of contract by one party, or a failure to perform.

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The net gain (loss) arising from the lessor's transactions involving the sale, transfer, or termination of financing agreements classified as capital leases.

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Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Commitments and contingencies: Gains on capital lease terminations (Details) - USD ($) $ in Thousands	1 Months Ended		12 Months Ended
	Jul. 31, 2015	Mar. 31, 2015	Dec. 31, 2015	Dec. 31, 2017	Dec. 31, 2016
Gains on capital lease terminations
Net book value				$ 381,282	$ 361,641
Gains on capital lease terminations			$ 11,643
Europe
Gains on capital lease terminations
Carrying value	$ 1,800
Settlement liability	(400)
Gains on capital lease terminations	$ 1,400
Spain
Gains on capital lease terminations
Estimate of possible loss		$ 9,000
Carrying value		29,900
Net book value		10,000
Gains on capital lease terminations		$ 10,100