Leases

The majority of the Company’s facilities are leased under non-cancellable operating leases ranging in terms from five to fifteen years and which contain renewal options of five to ten years at the fair rental value at the time of renewal. The Company’s leases are generally subject to periodic consumer price index increases or contain fixed escalation clauses. The Company also leases certain facilities and equipment under capital leases.

Future minimum lease payments under non-cancellable operating and capital leases are as follows:



	Operating leases		Capital leases
2018	$	446,935	$	35,258
2019	422,245		36,038
2020	384,764		36,689
2021	351,962		32,578
2022	313,005		33,004
Thereafter	1,303,594		234,094
	$	3,222,505	407,661
Less portion representing interest			(110,491		)
Total capital lease obligations, including current portion			$	297,170

Rent expense under all operating leases for 2017, 2016, and 2015 was $530,748, $478,531 and $440,601, respectively. Rent expense is recorded on a straight-line basis over the term of the lease for leases that contain fixed escalation clauses or include abatement provisions. Leasehold improvement incentives are deferred and amortized to rent expense over the term of the lease. The net book value of property and equipment under capital leases was $257,772 and $263,438 at December 31, 2017 and 2016, respectively. Capital lease obligations are included in long-term debt. See Note 13 to these consolidated financial statements.