Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Current assets:
Cash and cash equivalents	$ 270.1	$ 203.7
Trade and other accounts receivable (less allowances of $9.0 million and $10.3 million, respectively)	318.2	359.8
Inventories (less allowances of $26.4 million and $28.1 million, respectively):
Finished goods	216.5	215.7
Raw materials	87.8	84.4
Total inventories	304.3	300.1
Prepaid expenses	15.0	18.7
Prepaid income taxes	4.4	2.8
Other current assets	0.9	0.6
Total current assets	912.9	885.7
Net property, plant and equipment	268.7	268.3
Operating leases right-of-use assets	43.5	45.1
Goodwill	397.5	399.3
Other intangible assets	57.7	57.3
Deferred tax assets	10.4	10.4
Pension asset	36.1	35.1
Other non-current assets	6.0	6.2
Total assets	1,732.8	1,707.4
Current liabilities:
Accounts payable	166.4	163.6
Accrued liabilities	163.6	185.9
Current portion of operating lease liabilities	13.6	13.6
Current portion of plant closure provisions	4.6	4.6
Current portion of accrued income taxes	12.2	2.6
Current portion of unrecognized tax benefits	4.5	1.2
Total current liabilities	364.9	371.5
Operating lease liabilities, net of current portion	30.0	31.6
Plant closure provisions, net of current portion	56.6	57.0
Accrued income taxes, net of current portion	11.6	11.6
Unrecognized tax benefits, net of current portion	10.5	13.6
Deferred tax liabilities	34.1	33.5
Pension liabilities and post-employment benefits	13.0	13.3
Acquisition-related contingent consideration	23.5	23.4
Other non-current liabilities	2.4	2.3
Total liabilities	546.6	557.8
Equity:
Common stock, $0.01 par value, authorized 40,000,000 shares, issued 29,554,500 shares	0.3	0.3
Additional paid-in capital	362.4	361.0
Treasury stock (4,621,255 and 4,686,511 shares at cost, respectively)	(93.3)	(94.3)
Retained earnings	1,069.6	1,028.2
Accumulated other comprehensive loss	(155.4)	(148.1)
Total Innospec stockholders' equity	1,183.6	1,147.1
Non-controlling interest	2.6	2.5
Total equity	1,186.2	1,149.6
Total liabilities and equity	$ 1,732.8	$ 1,707.4

Prepaid Expense Current Excluding Tax

No definition available.

Name:	iosp_PrepaidExpenseCurrentExcludingTax
Namespace Prefix:	iosp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).