Earnings Per Share Attributable to Stockholders (Tables)

9 Months Ended

Sep. 30, 2018

Earnings Per Share Attributable to Stockholders [Abstract]

Computation of Basic and Diluted Earnings Per Share

	Three months ended					Nine months ended
	September 30, 2018					September 30, 2018
		Net income	WA				Net income	WA
		attributable to	number		Per share		attributable to	number		Per share
		stockholders	of shares		amount		stockholders	of shares		amount
Basic	$	23,138	108,365,427	$	0.21	$	85,993	107,811,391	$	0.80
Effect of dilutive securities:
Share units		-	551,313		-		-	408,006		-
Stock options		-	970,454		-		-	913,981		(0.01)
Diluted	$	23,138	109,887,194	$	0.21	$	85,993	109,133,378	$	0.79

	Three months ended					Nine months ended
	September 30, 2017					September 30, 2017
		Net income	WA				Net income	WA
		attributable to	number		Per share		attributable to	number		Per share
		stockholders	of shares		amount		stockholders	of shares		amount
Basic	$	10,261	107,120,618	$	0.10	$	38,273	106,993,358	$	0.36
Effect of dilutive securities:
Share units		-	214,304		-		(50)	337,570		-
Stock options		-	843,381		(0.01)		-	738,696		(0.01)
Diluted	$	10,261	108,178,303	$	0.09	$	38,223	108,069,624	$	0.35