Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Earnings Per Share [Abstract]
Net income attributable to the Company	$ 9,109	$ 29,190
Weighted average number of shares:
Weighted average number of shares used in calculating basic net income per share	32,312	32,272
Effect of dilutive stock-based compensation plans:
Stock options	8	13
Weighted average number of shares used in calculating diluted net income per share	32,320	32,285
Average market price of common stock used for calculation of dilutive shares	$ 65.47	$ 71.24
Net income attributable to the Company per share:
Basic	0.28	0.90
Diluted	$ 0.28	$ 0.90