Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Jun. 30, 2021	Jan. 01, 2021	Dec. 31, 2018
Summary Of Significant Accounting Policies [Line Items]
Investment owned at cost				$ 8,100,000
Ownership interest of investment owned				5.00%
Finite lived intangible assets impairment loss	$ 0	$ 0	$ 0
Offered period for sales return	30 days
Allowance for product returns	$ 600,000	600,000
Warranty reserve	30,401,000	22,075,000	$ 16,724,000			$ 9,138,000
Accumulated deficit	(634,595,000)	(659,210,000)
Convertible senior notes, net - long-term	$ 281,467,000	202,984,000
Slim cartridges and infusion sets
Summary Of Significant Accounting Policies [Line Items]
Warranty period offered	6 months
Insulin Pump
Summary Of Significant Accounting Policies [Line Items]
Warranty period offered	4 years
Technology-Based Intangible Assets
Summary Of Significant Accounting Policies [Line Items]
Estimated useful life	5 years
Cumulative Effect, Period of Adoption, Adjustment | Accounting Standards Update 2020-06
Summary Of Significant Accounting Policies [Line Items]
Accumulated deficit					$ 9,000,000
Additional paid in capital					(85,800,000)
Convertible senior notes, net - long-term					$ 76,800,000
Minimum
Summary Of Significant Accounting Policies [Line Items]
Estimated useful lives of the assets	3 years
Maximum
Summary Of Significant Accounting Policies [Line Items]
Estimated useful lives of the assets	7 years
Convertible senior notes | Level 2 | Convertible senior notes
Summary Of Significant Accounting Policies [Line Items]
Convertible senior notes, fair value	$ 430,000,000	$ 333,500,000