Significant accounting policies (Tables)

12 Months Ended

Dec. 31, 2013

Accounting Policies [Abstract]

Summary of Estimated Useful Lives of Property and Equipment

Depreciation of property and equipment is provided on a straight-line basis from the date assets are put in service over their estimated useful lives as follows:

Buildings	30 years
Leasehold interests and improvements	Over term of lease
Vehicles:
Trailers and containers	12 years
Trucks	8 years
Machinery and equipment	4 - 10 years

Summary of Accounts Payable and Accrued Liabilities

Accounts payable and accrued liabilities:

	2013		2012
Accounts payable	$	15,439	$	18,398
Accrued wages and benefits		1,302		1,452
Accrued claims, self-insurance and workers’ compensation		844		698
Other		5,233		3,598
	$	22,818	$	24,146