Stockholders' Equity - Stock Options Granted (Details)	95 Months Ended
	Mar. 31, 2019 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Granted (in shares)	6,510,879
Options Outstanding (in shares)	4,270,442
Options Exercisable (in shares)	1,440,687
January 2, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Granted (in shares)	658,462
Option Exercise (Strike) Price (in dollars per share) | $ / shares	$ 52
Closing Stock Price on Date of Grant (in dollars per share) | $ / shares	$ 51.41
Options Outstanding (in shares)	657,118
Options Exercisable (in shares)	14,505
January 2, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Granted (in shares)	543,968
Option Exercise (Strike) Price (in dollars per share) | $ / shares	$ 55
Closing Stock Price on Date of Grant (in dollars per share) | $ / shares	$ 54.54
Options Outstanding (in shares)	519,349
Options Exercisable (in shares)	21,185
January 3, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Granted (in shares)	764,789
Option Exercise (Strike) Price (in dollars per share) | $ / shares	$ 47
Closing Stock Price on Date of Grant (in dollars per share) | $ / shares	$ 46.95
Options Outstanding (in shares)	646,854
Options Exercisable (in shares)	206,755
April 19, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Granted (in shares)	845,440
Option Exercise (Strike) Price (in dollars per share) | $ / shares	$ 46
Closing Stock Price on Date of Grant (in dollars per share) | $ / shares	$ 45.74
Options Outstanding (in shares)	668,947
Options Exercisable (in shares)	185,055
April 21, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Granted (in shares)	893,220
Option Exercise (Strike) Price (in dollars per share) | $ / shares	$ 42
Closing Stock Price on Date of Grant (in dollars per share) | $ / shares	$ 41.26
Options Outstanding (in shares)	575,476
Options Exercisable (in shares)	142,607
April 22, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Granted (in shares)	955,000
Option Exercise (Strike) Price (in dollars per share) | $ / shares	$ 56
Closing Stock Price on Date of Grant (in dollars per share) | $ / shares	$ 50.53
Options Outstanding (in shares)	445,900
Options Exercisable (in shares)	266,900
April 16, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Granted (in shares)	205,000
Option Exercise (Strike) Price (in dollars per share) | $ / shares	$ 54
Closing Stock Price on Date of Grant (in dollars per share) | $ / shares	$ 49.25
Options Outstanding (in shares)	74,435
Options Exercisable (in shares)	42,567
April 17, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Granted (in shares)	1,235,000
Option Exercise (Strike) Price (in dollars per share) | $ / shares	$ 54
Closing Stock Price on Date of Grant (in dollars per share) | $ / shares	$ 49.01
Options Outstanding (in shares)	643,713
Options Exercisable (in shares)	534,963
April 19, 2011
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	$ 35
Closing Stock Price on Date of Grant (in dollars per share) | $ / shares	$ 31.78
Options Outstanding (in shares)	38,650
Options Exercisable (in shares)	26,150