Other long-term liabilities:



As at	Dec 31 2017			Dec 31 2016
Site restoration costs^(a)	$	33,975		$	30,512
Finance lease obligations^(b)	204,242			201,268
Share-based compensation liability (note 13)	111,405			53,725
Cash flow hedges (note 18)	90,199			68,664
Defined benefit pension plans (note 20)	25,076			22,403
Other	5,214			4,339
	470,111			380,911
Less current maturities	(65,226		)	(29,720		)
	$	404,885		$	351,191

a) Site restoration costs:

The Company has accrued liabilities related to the decommissioning and reclamation of its methanol production sites and oil and gas properties. Because of uncertainties in estimating the amount and timing of the expenditures related to the sites, actual results could differ from the amounts estimated. As at December 31, 2017, the total undiscounted amount of estimated cash flows required to settle the liabilities was $44.9 million (2016 - $41.1 million). The movement in the provision during the year is explained as follows:



	2017		2016
Balance at January 1	$	30,512	$	29,892
New or revised provisions	2,823		51
Accretion expense	640		569
Balance at December 31	$	33,975	$	30,512

b) Finance lease obligations:

As at December 31, 2017, the Company has finance lease obligations related to a methanol terminal and storage tanks in Geismar, Louisiana, an oxygen production facility in Trinidad, and two ocean-going vessels. Total finance lease payments for 2017 of $30.6 million include an interest component of $23.7 million.

Finance lease obligations are payable as follows:



	Lease payments		Interest component		Finance lease obligations
2018	$	31,447	$	23,549	$	7,898
2019	31,826		22,727		9,099
2020	32,213		21,756		10,457
2021	32,608		20,612		11,996
2022	33,010		19,271		13,739
Thereafter	236,772		85,719		151,053
	$	397,876	$	193,634	$	204,242