Stockholders' Equity - Stock Options Granted (Details)	98 Months Ended
	Jun. 30, 2019 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Granted (in shares)	13,021,758
Options Outstanding (in shares)	7,637,201
Options Exercisable (in shares)	2,625,361
January 2, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Granted (in shares)	1,316,924
Option Exercise (Strike) Price (in dollars per share) | $ / shares	$ 26.00
Closing Stock Price on Date of Grant (in dollars per share) | $ / shares	$ 25.705
Options Outstanding (in shares)	1,303,670
Options Exercisable (in shares)	29,010
January 2, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Granted (in shares)	1,087,936
Option Exercise (Strike) Price (in dollars per share) | $ / shares	$ 27.50
Closing Stock Price on Date of Grant (in dollars per share) | $ / shares	$ 27.270
Options Outstanding (in shares)	1,033,248
Options Exercisable (in shares)	42,370
January 3, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Granted (in shares)	1,529,578
Option Exercise (Strike) Price (in dollars per share) | $ / shares	$ 23.50
Closing Stock Price on Date of Grant (in dollars per share) | $ / shares	$ 23.475
Options Outstanding (in shares)	1,247,616
Options Exercisable (in shares)	371,622
April 19, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Granted (in shares)	1,690,880
Option Exercise (Strike) Price (in dollars per share) | $ / shares	$ 23.00
Closing Stock Price on Date of Grant (in dollars per share) | $ / shares	$ 22.870
Options Outstanding (in shares)	1,286,260
Options Exercisable (in shares)	327,170
April 21, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Granted (in shares)	1,786,440
Option Exercise (Strike) Price (in dollars per share) | $ / shares	$ 21.00
Closing Stock Price on Date of Grant (in dollars per share) | $ / shares	$ 20.630
Options Outstanding (in shares)	975,939
Options Exercisable (in shares)	463,383
April 22, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Granted (in shares)	1,910,000
Option Exercise (Strike) Price (in dollars per share) | $ / shares	$ 28.00
Closing Stock Price on Date of Grant (in dollars per share) | $ / shares	$ 25.265
Options Outstanding (in shares)	743,716
Options Exercisable (in shares)	494,356
April 16, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Granted (in shares)	410,000
Option Exercise (Strike) Price (in dollars per share) | $ / shares	$ 27.00
Closing Stock Price on Date of Grant (in dollars per share) | $ / shares	$ 24.625
Options Outstanding (in shares)	118,094
Options Exercisable (in shares)	76,844
April 17, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Granted (in shares)	2,470,000
Option Exercise (Strike) Price (in dollars per share) | $ / shares	$ 27.00
Closing Stock Price on Date of Grant (in dollars per share) | $ / shares	$ 24.505
Options Outstanding (in shares)	872,358
Options Exercisable (in shares)	764,306
April 19, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Granted (in shares)	820,000
Option Exercise (Strike) Price (in dollars per share) | $ / shares	$ 17.50
Closing Stock Price on Date of Grant (in dollars per share) | $ / shares	$ 15.890
Options Outstanding (in shares)	56,300
Options Exercisable (in shares)	56,300