Leases (Tables)

12 Months Ended

Dec. 31, 2014

Leases [Abstract]

Future Minimum Lease Payments

The future minimum lease payments are summarized as follows (in thousands of dollars):

2015	48,387
2016	38,857
2017	33,179
2018	27,300
2019	20,140
2020 and after	18,316
	186,179