Leases

The Company leases equipment, land and various other properties under non-cancelable long-term leases, expiring at various dates. Certain leases contain options that would allow the Company to extend the lease or purchase the leased asset at the end of the base lease term.

In addition, the Company enters into various non-cancelable royalty lease agreements under which future minimum payments are due.

Minimum payments due in future years under these agreements in effect at December 31, 2015 are as follows:



	Operating
	Leases		Royalties
	(In thousands)
2016	$	20,857	$	8,947
2017	17,277		13,991
2018	6,412		13,097
2019	3,448		12,295
2020	2,151		11,996
Thereafter	9,807		103,771
	$	59,952	$	164,097

Obligations for the future minimum payments under capital leases for equipment totaling $40.0 million and $46.0. million at December 31, 2015 and 2014, respectively, are included in other long term debt obligations in Note 14, "Debt and Financing Arrangements".

Rental expense, including amounts related to these operating leases and other shorter-term arrangements, amounted to $28.4 million in 2015, $42.1 million in 2014 and $42.1 million in 2013.

Royalties are paid to lessors either as a fixed price per ton or as a percentage of the gross selling price of the mined coal. Royalties under the majority of the Company's significant leases are paid on the percentage of gross selling price basis. Royalty expense, including production royalties, was $227.7 million in 2015, $242.5 million in 2014 and $261.1 million in 2013.

As of December 31, 2015, certain of the Company's lease obligations were secured by outstanding surety bonds totaling $49.4 million.