STOCKHOLDERS' EQUITY - Schedule of Stockholders Equity (Details) - USD ($) shares in Thousands, $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Jan. 01, 2019
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance (in shares)			114,500
Beginning balance	$ 7,279.6	$ 5,869.2	$ 6,687.5	$ 4,780.4
Adoption of new accounting standards					$ 390.8
Issuance of common stock through employee stock plans	86.1	64.7	205.7	199.6
Shares withheld related to net share settlement of equity awards	(7.9)	(7.0)	(152.9)	(115.0)
Share-based compensation expense related to employee stock plans	88.9	70.1	246.6	190.9
Repurchase and retirement of common stock	(69.5)		(269.5)
Net income attributable to Intuitive Surgical, Inc.	396.8	292.5	1,021.6	835.4
Other comprehensive income	1.2	(0.3)	30.6	0.1
Capital contribution from noncontrolling interest			10.0	8.0
Less: net loss attributable to noncontrolling interest in joint venture	$ 1.9	(0.7)	$ (2.5)	(1.7)
Ending balance (in shares)	115,600		115,600
Ending balance	$ 7,777.1	$ 6,288.5	$ 7,777.1	$ 6,288.5
Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance (in shares)	115,200	113,700	114,500	112,300
Beginning balance	$ 0.1	$ 0.1	$ 0.1	$ 0.1
Issuance of common stock through employee stock plans (in shares)	600	500	2,000	2,200
Shares withheld related to net share settlement of equity awards	0	0	(300)	(300)
Repurchase and retirement of common stock (in shares)	(200)		(600)
Ending balance (in shares)	115,600	114,200	115,600	114,200
Ending balance	$ 0.1	$ 0.1	$ 0.1	$ 0.1
Additional Paid-In Capital
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	5,430.1	4,928.8	5,170.3	4,679.2
Issuance of common stock through employee stock plans	86.1	64.7	205.7	199.6
Shares withheld related to net share settlement of equity awards	(0.5)	(0.4)	(7.2)	(6.5)
Share-based compensation expense related to employee stock plans	88.9	70.1	246.6	190.9
Repurchase and retirement of common stock	(3.7)		(14.5)
Ending balance	5,600.9	5,063.2	5,600.9	5,063.2
Retained Earnings
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	1,819.0	948.1	1,521.7	115.0
Adoption of new accounting standards					392.1
Shares withheld related to net share settlement of equity awards	(7.4)	(6.6)	(145.7)	(108.5)
Repurchase and retirement of common stock	(65.8)		(255.0)
Net income attributable to Intuitive Surgical, Inc.	396.8	292.5	1,021.6	835.4
Ending balance	2,142.6	1,234.0	2,142.6	1,234.0
Accumulated Other Comprehensive Income (Loss)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	16.1	(16.4)	(13.3)	(15.5)
Adoption of new accounting standards					(1.3)
Other comprehensive income	1.7	(0.3)	31.1	0.1
Ending balance	17.8	(16.7)	17.8	(16.7)
Total Intuitive Surgical, Inc. Stockholders’ Equity
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	7,265.3	5,860.6	6,678.8	4,778.8
Adoption of new accounting standards					$ 390.8
Issuance of common stock through employee stock plans	86.1	64.7	205.7	199.6
Shares withheld related to net share settlement of equity awards	(7.9)	(7.0)	(152.9)	(115.0)
Share-based compensation expense related to employee stock plans	88.9	70.1	246.6	190.9
Repurchase and retirement of common stock	(69.5)		(269.5)
Net income attributable to Intuitive Surgical, Inc.	396.8	292.5	1,021.6	835.4
Other comprehensive income	1.7	(0.3)	31.1	0.1
Ending balance	7,761.4	6,280.6	7,761.4	6,280.6
Noncontrolling Interest in Joint Venture
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	14.3	8.6	8.7	1.6
Other comprehensive income	(0.5)		(0.5)
Capital contribution from noncontrolling interest			10.0	8.0
Less: net loss attributable to noncontrolling interest in joint venture	1.9	(0.7)	(2.5)	(1.7)
Ending balance	$ 15.7	$ 7.9	$ 15.7	$ 7.9

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