Stock-Based Compensation - Schedule of Grants (Details) - shares	Jun. 30, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Outstanding (in shares)	264,246	264,246
RSUs Outstanding (in shares)	1,389,167
Options and RSUs Exercised (in shares)	4,627,450
Available Shares (in shares)	2,064,988
Total (in shares)	8,345,851
2017 ECP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Outstanding (in shares)	0
RSUs Outstanding (in shares)	846,273
Options and RSUs Exercised (in shares)	41,664
Available Shares (in shares)	1,412,063
Total (in shares)	2,300,000
2010 ECP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Outstanding (in shares)	250,498
RSUs Outstanding (in shares)	542,894
Options and RSUs Exercised (in shares)	3,635,701
Available Shares (in shares)	652,925
Total (in shares)	5,082,018
2005 LTIP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Outstanding (in shares)	13,748
RSUs Outstanding (in shares)	0
Options and RSUs Exercised (in shares)	950,085
Available Shares (in shares)	0
Total (in shares)	963,833