Net Income (Loss) Per Common Share (Dilutive Common Share Equivalents) (Details) - shares	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Weighted-average common shares outstanding, basic (in shares)	75,539,535	73,977,241
Effect of dilutive securities (in shares)	3,575,502	0
Weighted-average common shares outstanding, diluted (in shares)	79,115,037	73,977,241
RSUs and PRSUs
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Effect of dilutive securities (in shares)	1,024,301	0
Stock options
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Effect of dilutive securities (in shares)	2,549,887	0
Employee stock purchase plan
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Effect of dilutive securities (in shares)	1,314	0