Consolidated Statements of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Cash flows from operating activities:
income (loss)	$ 3,953.2	$ (535.6)	$ 3,619.6
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Stock-based compensation expense	685.9	698.5	581.2
Depreciation and amortization expense	209.8	207.2	181.3
Intangible asset impairment charges	379.0	0.0	0.0
Deferred income taxes	(510.8)	(348.8)	(536.5)
Other non-cash items, net	113.4	0.9	(42.6)
Changes in operating assets and liabilities:
Accounts receivable, net	(347.3)	(99.3)	(84.1)
Inventories	(524.2)	(517.3)	(322.9)
Prepaid expenses and other assets	(396.0)	(200.3)	(545.7)
Accounts payable	36.8	49.5	48.7
Accrued expenses	(116.9)	212.9	429.4
Other liabilities	148.5	39.7	208.9
Net cash provided by (used in) operating activities	3,631.4	(492.6)	3,537.3
Cash flows from investing activities:
Purchases of available-for-sale debt securities	(6,396.5)	(7,438.2)	(3,786.5)
Sales and maturities of available-for-sale debt securities	5,897.4	4,465.6	839.1
Purchases of property and equipment	(437.6)	(297.7)	(200.4)
Proceeds related to equity securities	16.0	0.0	95.1
Net payments related to finite-lived intangible assets	0.0	(187.7)	(58.0)
Acquisition of available-for-sale debt securities from Alpine Immune Sciences, Inc.	0.0	(258.0)	0.0
Other investing activities	(24.7)	(54.0)	(31.0)
Net cash used in investing activities	(945.4)	(3,770.0)	(3,141.7)
Cash flows from financing activities:
Issuances of common stock under benefit plans	127.7	114.6	134.6
Repurchases of common stock	(2,017.4)	(1,177.1)	(427.6)
Payments in connection with common stock withheld for employee tax obligations	(369.9)	(405.0)	(226.1)
Payments on finance leases	(5.4)	(33.6)	(44.9)
Other financing activities	3.7	6.2	1.8
Net cash used in financing activities	(2,261.3)	(1,494.9)	(562.2)
Effect of changes in exchange rates on cash	90.9	(42.6)	26.9
Net increase (decrease) in cash, cash equivalents and restricted cash	515.6	(5,800.1)	(139.7)
Cash, cash equivalents and restricted cash—beginning of period	4,572.2	10,372.3	10,512.0
Cash, cash equivalents and restricted cash—end of period	5,087.8	4,572.2	10,372.3
Supplemental disclosure of cash flow information:
Cash paid for income taxes	1,566.7	1,082.1	1,677.3
Cash paid for interest	12.4	30.5	43.1
Net payments due to CRISPR Therapeutics AG related to finite-lived intangible assets	$ 0.0	$ 0.0	$ 180.0