Other Assets (Tables)

12 Months Ended

Dec. 31, 2016

Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]

Schedule of Company's Other Assets

The following table summarizes the Company’s other assets at December 31 of the following years:

	2016		2015
	(Thousands of dollars)
Deposits on future purchases of aircraft	$	4,818	$	3,568
Investment in Variable Interest Entity		1,351		—
Investments (Officers’ Deferred Compensation Plan)		2,394		2,294
Other		1,196		316
Total	$	9,759	$	6,178