Other information

a) Supplemental cash flow information



Year ended December 31,	2018		2017
Cash paid during the year for:
Interest	$	9,258	$	5,615
Cash received during the year for:
Interest	41		162



Year ended December 31,	2018		2017
Non-cash transactions:
Addition of property, plant and equipment by means of capital leases	49,440		34,730
Property, plant and equipment reclassified to asset held for sale	(53	)	(6,869	)
Increase in capital lease obligations related to purchase of heavy equipment fleet and related assets	1,759		—
Increase in capital lease obligations related to investment in affiliates and joint ventures	542		—
Increase in capital lease obligations related to the initial investment in the partnership	—		800
Increase in equipment promissory notes related to purchase of heavy equipment fleet and related assets	10,851		—
Acquisition of property, plant and equipment related to the initial investment in the partnership	—		2,581
Increase in long term debt related to the initial investment in the partnership	—		637
Increase in long term debt related to investment in affiliates and joint ventures	3,127		—
Non-cash working capital exclusions:
Decrease in contract assets related to adoption of accounting standards	(547	)	—
Increase in inventory related to the initial partnership investment	—		29
Increase in inventory related to the purchase of heavy equipment fleet and related assets	4,268		—
Increase in prepaid expenses related to the initial investment in the partnership	—		4
Increase in other assets related to adoption of accounting standards	502		—
Increase in accrued liabilities related to the current portion of the deferred gain on sale-leaseback	—		(859	)
Decrease in accrued liabilities related to conversion of bonus compensation to deferred stock units	326		—
Decrease in accrued liabilities related to dividend payable	10		59
Non-cash working capital transactions related to investments in affiliates and joint ventures:
Increase in accounts receivable	13,234		—
Increase in contract assets	3,089		—
Increase in inventory	3,926		—
Increase in prepaid expenses	399		—
Increase in accounts payable	(10,604	)	—
Increase in accrued liabilities	(1,136	)	—
Increase in contract liabilities	(360	)	—

b) Net change in non-cash working capital

The table below represents the cash (used in) provided by non-cash working capital:



Year ended December 31,	2018			2017
Operating activities:
Accounts receivable	$	(22,359	)	$	(7,148	)
Contract assets	13,441			(5,607		)
Inventories	(443		)	(1,288		)
Contract costs	(1,384		)	—
Prepaid expenses and deposits	(1,513		)	(283		)
Accounts payable	17,665			5,640
Accrued liabilities	5,923			1,904
Contract liabilities	2,848			(247		)
	$	14,178		$	(7,029	)