Business Combinations (Schedule of Pro Forma) (Details) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2018 USD ($) $ / shares
Business Combinations [Abstract]
Revenues, net | $	$ 799,137
Income from continuing operations, net of income taxes | $	$ 148,210
Net income per share, basic | $ / shares	$ 2.43
Net income per share, diluted | $ / shares	$ 2.40