14. Leases

Operating lease rental income for leased assets is recognized on a straight‑line basis and amounted to $8.3 million, $9.7 million and $9.4 million for the years ended December 31, 2017, 2016 and 2015, respectively. Related depreciation expense for owned properties is recorded in occupancy expense on a straight‑line basis over the properties’ estimated useful lives.

The following table sets forth future minimum rental income under noncancelable operating leases with terms in excess of one year as of December 31, 2017:


	Minimum
	Rental
(dollars in thousands)	Income
Year ending December 31:
2018	$	5,642
2019		5,642
2020		5,638
2021		5,564
2022		4,550
Thereafter		11,072
Total	$	38,108

The Company, as lessee, is obligated under a number of noncancelable operating leases for premises and equipment with terms, including renewal options, up to 46 years, many of which provide for periodic adjustment of rent payments based on changes in various economic indicators. Under the premises leases, the Company is usually required to pay real property taxes, insurance and maintenance.

Rental expense, net of sublease income, was as follows:


	Year Ended December 31,
(dollars in thousands)	2017		2016		2015
Rental expense charged to occupancy	$	8,620	$	8,689	$	8,698
Less: sublease income		1,342		1,303		1,588
Net rental expense charged to occupancy		7,278		7,386		7,110
Rental expense charged to equipment expense		285		326		383
Total	$	7,563	$	7,712	$	7,493

The following table presents future minimum rental expense under leases with terms in excess of one year as of December 31, 2017:


	Operating		Less		Net
	Lease		Sublease		Lease
(dollars in thousands)	Payments		Income		Payments
Year ending December 31:
2018	$	7,694	$	893	$	6,801
2019		7,449		893		6,556
2020		6,823		893		5,930
2021		5,184		881		4,303
2022		2,557		—		2,557
Thereafter		18,004		—		18,004
Total	$	47,711	$	3,560	$	44,151