Share Capital (Tables)

12 Months Ended

Dec. 31, 2017

Equity [Abstract]

Changes in Number of Shares of Class A Stock Outstanding

The following table reflects changes in the number of shares of Class A Stock outstanding for the periods indicated:

	2017		2016
Class A Stock outstanding, beginning of year	13,261,095		13,238,486
Issued pursuant to shared-based compensation plans (note 14)	328,458		283,471
Repurchased and canceled pursuant to the stock buy-back	(450,350	)	(260,862	)
Class A Stock outstanding, end of year	13,139,203		13,261,095