Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 2,898.2	$ 3,419.3
Marketable securities	2,143.1	1,473.5
Accounts receivable, net	1,634.4	1,705.0
Due from anti-CD20 therapeutic programs	393.8	431.4
Inventory	1,281.0	1,344.4
Other current assets	1,412.0	1,417.6
Total current assets	9,762.5	9,791.2
Marketable securities	978.2	705.7
Property, plant and equipment, net	3,300.9	3,298.6
Operating lease assets	399.1	403.9
Intangible assets, net	1,813.3	1,850.1
Goodwill	5,751.8	5,749.0
Deferred tax asset	1,211.8	1,226.4
Investments and other assets	1,380.8	1,529.2
Total assets	24,598.4	24,554.1
Current liabilities:
Taxes payable	235.5	259.9
Accounts payable	491.2	491.5
Accrued expense and other	2,288.2	2,521.4
Total current liabilities	3,014.9	3,272.8
Notes payable	6,282.7	6,281.0
Deferred tax liability	251.3	334.7
Long-term operating lease liabilities	327.0	333.0
Other long-term liabilities	935.5	944.2
Total liabilities	10,811.4	11,165.7
Commitments, contingencies and guarantees
Biogen Idec Inc. shareholders' equity
Preferred stock, par value $0.001 per share	0.0	0.0
Common stock, par value $0.0005 per share	0.1	0.1
Additional paid-in capital	91.2	73.3
Accumulated other comprehensive income (loss)	(172.0)	(164.9)
Retained earnings	16,854.4	16,466.5
Treasury stock, at cost	(2,977.1)	(2,977.1)
Total Biogen Inc. shareholders’ equity	13,796.6	13,397.9
Noncontrolling interests	(9.6)	(9.5)
Total equity	13,787.0	13,388.4
Total liabilities and equity	$ 24,598.4	$ 24,554.1