Innospec (IOSP) 10-K 13 Feb 14 2013 FY Annual report Financial data

Document_and_Entity_Informatio

Document and Entity Information (USD $)	12 Months Ended
In Millions, except Share data, unless otherwise specified	Dec. 31, 2013	Feb. 06, 2014	Jun. 30, 2013
Document And Entity Information [Abstract]	'	'	'
Document Type	'10-K	'	'
Amendment Flag	'false	'	'
Document Period End Date	31-Dec-13	'	'
Document Fiscal Year Focus	'2013	'	'
Document Fiscal Period Focus	'FY	'	'
Trading Symbol	'IOSP	'	'
Entity Registrant Name	'INNOSPEC INC.	'	'
Entity Central Index Key	'0001054905	'	'
Current Fiscal Year End Date	'--12-31	'	'
Entity Well-known Seasoned Issuer	'No	'	'
Entity Current Reporting Status	'Yes	'	'
Entity Voluntary Filers	'No	'	'
Entity Filer Category	'Accelerated Filer	'	'
Entity Common Stock, Shares Outstanding	'	24,346,553	'
Entity Public Float	'	'	$515

Consolidated_Statements_of_Inc

Consolidated Statements of Income (USD $)	12 Months Ended
In Millions, except Share data in Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Statement [Abstract]	'	'	'
Net sales	$818.80	$776.40	$774.40
Cost of goods sold	-563.6	-540	-548
Gross profit	255.2	236.4	226.4
Operating expenses:	'	'	'
Selling, general and administrative	-141.9	-119	-158.3
Research and development	-21.2	-19.6	-18.3
Restructuring charge	-0.2	-0.2	-0.6
Impairment of Octane Additives segment goodwill	-1.3	-1.2	-2
Profit on disposal, net	0	0.1	0
Total operating expenses	-164.6	-139.9	-179.2
Operating income	90.6	96.5	47.2
Other net income/(expense)	4.1	-2	6.3
Interest expense	-2.3	-1.8	-3.9
Interest income	0.4	0.6	0.6
Income before income taxes	92.8	93.3	50.2
Income taxes	-15	-26.4	-3.1
Net income	$77.80	$66.90	$47.10
Earnings per share:	'	'	'
Basic	$3.29	$2.89	$2
Diluted	$3.22	$2.81	$1.92
Weighted average shares outstanding (in thousands):	'	'	'
Basic	23,651	23,187	23,568
Diluted	24,156	23,850	24,520
Dividend declared per common share	$0.50	$2	$0

Consolidated_Statements_of_Com

Consolidated Statements of Comprehensive Income (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Statement Of Income And Comprehensive Income [Abstract]	'		'		'
Net income	$77.80		$66.90		$47.10
Changes in cumulative translation adjustment	1.2		7.2		-3.9
Changes in unrealized gains/(losses) on derivative instruments, net of tax of $0.0 million, $0.0 million and $0.3 million, respectively	-0.1		-0.1		-0.7
Deferred taxes	0	[1]	0	[1]	-2.6	[1],[2]
Amortization of prior service credit, net of tax of $0.3 million, $0.3 million and $0.4 million, respectively	-1		-1		-0.9
Amortization of actuarial net losses, net of tax of $(1.4) million, $(0.8) million and $(0.7) million, respectively	4.8		2.4		2
Actuarial net (losses)/gains arising during the year, net of tax of $1.8 million, $17.8 million and $(6.6) million, respectively	-6.7		-58.5		19.5
Total comprehensive income	$76		$16.90		$60.50
[1]	Impact on deferred taxes during the year ended December 31, 2011 of a change in the associated tax rate on the unrecognized actuarial net losses.
[2]	Impact on deferred taxes of a change in the associated tax rate on the unrecognized actuarial net losses.

Consolidated_Statements_of_Com1

Consolidated Statements of Comprehensive Income (Parenthetical) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Statement Of Income And Comprehensive Income [Abstract]	'	'	'
Changes in unrealized gains/(losses) on derivative instruments, tax	$0	$0	$0.30
Amortization of prior service credit, tax	0.3	0.3	0.4
Amortization of actuarial net losses, tax	-1.4	-0.8	-0.7
Actuarial net (losses)/gains, tax	$1.80	$17.80	($6.60)

Accumulated_Other_Comprehensiv

Accumulated Other Comprehensive Loss (USD $)	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
In Millions, unless otherwise specified
Accumulated Other Comprehensive Income Loss Net Of Tax [Abstract]	'	'	'
Cumulative translation adjustment	($33.70)	($34.90)	($42.10)
Unrealized gains on derivative instruments, net of tax of $0.0 million, $0.0 million and $0.0 million, respectively	0	0.1	0.2
Unrecognized actuarial net losses, net of tax of $36.9 million, $36.2 million and $18.9 million, respectively	-120.2	-117.3	-60.2
Accumulated other comprehensive loss	($153.90)	($152.10)	($102.10)

Accumulated_Other_Comprehensiv1

Accumulated Other Comprehensive Loss (Parenthetical) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Accumulated Other Comprehensive Income Loss Net Of Tax [Abstract]	'	'	'
Unrealized gains on derivative instruments, tax	$0	$0	$0
Unrecognized actuarial net losses, tax	$36.90	$36.20	$18.90

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Current assets:	'	'
Cash and cash equivalents	$80.20	$22.40
Short-term investments	6.6	5.1
Trade and other accounts receivable (less allowances of $2.0 and $1.9, respectively)	135.8	115.7
Inventories (less allowances of $9.5 and $8.9, respectively):	'	'
Finished goods	95.3	75.2
Work in progress	1.9	1.5
Raw materials	61.7	61.6
Total inventories	158.9	138.3
Current portion of deferred tax assets	8.7	11
Prepaid expenses	5.8	4.1
Prepaid income taxes	11.4	0
Total current assets	407.4	296.6
Property, plant and equipment	60.4	49.8
Goodwill	187.9	149
Other intangible assets	126.8	68.6
Deferred finance costs	1.8	1.3
Deferred tax assets, net of current portion	8.6	12.7
Other non-current assets	1.8	1.4
Total assets	794.7	579.4
Current liabilities:	'	'
Accounts payable	63.3	57.3
Accrued liabilities	73.5	72.1
Accrued income taxes	0	3.2
Current portion of long-term debt	5.3	5
Current portion of plant closure provisions	6.2	5.1
Current portion of unrecognized tax benefits	6.8	3
Current portion of deferred tax liabilities	0.2	0.2
Current portion of deferred income	0.3	1.4
Total current liabilities	155.6	147.3
Long-term debt, net of current portion	142.7	25
Plant closure provisions, net of current portion	26.2	25.3
Unrecognized tax benefits, net of current portion	6.2	9.8
Deferred tax liabilities, net of current portion	9.5	3.6
Pension liabilities	39	46
Acquisition-related contingent consideration	4.6	4.3
Other non-current liabilities	0.3	0.2
Deferred income, net of current portion	1.2	0.9
Stockholders' 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	308.8	292.1
Treasury stock (5,207,947 and 6,222,076 shares at cost, respectively)	-73.3	-85
Retained earnings	327.5	261.7
Accumulated other comprehensive loss	-153.9	-152.1
Total stockholders' equity	409.4	317
Total liabilities and stockholders' equity	$794.70	$579.40

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets (Parenthetical) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Millions, except Share data, unless otherwise specified
Statement Of Financial Position [Abstract]	'	'
Allowances for doubtful accounts	$2	$1.90
Inventory allowances	$9.50	$8.90
Common stock, par value	$0.01	$0.01
Common stock, shares authorized	40,000,000	40,000,000
Common stock, shares issued	29,554,500	29,554,500
Treasury stock, shares	5,207,947	6,222,076

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Cash Flows from Operating Activities	'		'		'
Net income	$77.80		$66.90		$47.10
Adjustments to reconcile net income to net cash provided by operating activities:	'		'		'
Depreciation and amortization	20.4	[1]	11.5	[1]	14.4	[1]
Impairment of Octane Additives segment goodwill	1.3		1.2		2
Deferred taxes	5.8		12.1		-4.6
Excess tax benefit from stock based payment arrangements	-3.8		-2.2		-1.1
Profit on disposal of property, plant and equipment, net	0		-0.1		0
Cash contributions to defined benefit pension plans	-11		-9.4		-9.5
Non-cash expense of defined benefit pension plans	3		2		3.4
Stock option compensation	2.5		3.1		3.1
(Repayment)/issue of promissory note in civil complaint settlement	-5		-5		15
Non-cash issue of treasury stock in civil complaint settlement	0		0		5
Changes in assets and liabilities, net of effects of acquired and divested companies:	'		'		'
Trade and other accounts receivable	-1.4		-14.1		-15.3
Inventories	-10.1		-1		-14.3
Prepaid expenses	-0.5		0.1		0
Accounts payable and accrued liabilities	-4.4		-5.5		-13.7
Accrued income taxes	-14.7		1		-4.1
Plant closure provisions	1.9		1.8		1.1
Unrecognized tax benefits	0.2		0.2		4
Other non-current assets and liabilities	-0.7		-1.3		2.2
Net cash provided by/(used in) operating activities	61.3		61.3		34.7
Cash Flows from Investing Activities	'		'		'
Capital expenditures	-11.1		-8.8		-7
Business combinations, net of cash acquired	-94.4		-53.1		0
Internally developed software and other costs	-9.4		-8.5		-3.1
Proceeds on disposal of property, plant and equipment	0.1		0.2		0
Purchase of short-term investments	-7		-5		-5
Sale of short-term investments	5.7		4.9		4.4
Net cash provided by/(used in) investing activities	-116.1		-70.3		-10.7
Cash Flows from Financing Activities	'		'		'
Proceeds from revolving credit facility	145		18		51
Repayments of revolving credit facility	-23		-18		-38
Repayment of term loans	-0.2		0		-40
Refinancing costs	-0.9		0		-1.7
Excess tax benefit from stock based payment arrangements	3.8		2.2		1.1
Dividend paid	-12		-46.7		0
Issue of treasury stock	3.8		1.2		0.7
Repurchase of common stock	-3.7		-1.4		-28.1
Net cash provided by/(used in) financing activities	112.8		-44.7		-55
Effect of foreign currency exchange rate changes on cash	-0.2		-0.1		0.1
Net change in cash and cash equivalents	57.8		-53.8		-30.9
Cash and cash equivalents at beginning of year	22.4		76.2		107.1
Cash and cash equivalents at end of year	$80.20		$22.40		$76.20
[1]	Amortization of deferred finance costs of $0.4 million (2012 - $0.4 million, 2011 - $0.5 million) for the year are included in depreciation and amortization in the cash flow statement but in interest expense in the income statement. Cash payments/receipts in respect of income taxes and interest are disclosed in Note 10 and Note 11, respectively.

Consolidated_Statements_of_Cas1

Consolidated Statements of Cash Flows (Parenthetical) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Statement Of Cash Flows [Abstract]	'	'	'
Amortization of deferred finance costs	$0.40	$0.40	$0.50

Consolidated_Statements_of_Sto

Consolidated Statements of Stockholders' Equity (USD $)

Total

Bachman [Member]

Chemsil [Member]

Common Stock [Member]

Additional Paid-In Capital [Member]

Additional Paid-In Capital [Member]

Additional Paid-In Capital [Member]

Treasury Stock [Member]

Treasury Stock [Member]

Treasury Stock [Member]

Retained Earnings [Member]

Accumulated Other Comprehensive Loss [Member]

In Millions

Bachman [Member]

Chemsil [Member]

Bachman [Member]

Chemsil [Member]

Beginning Balance at Dec. 31, 2010

$300.70

'

'

$0.30

$286.30

'

'

($64.80)

'

'

$210.50

($131.60)

Revision of prior period (Note 2)

0

'

'

'

'

'

'

'

'

'

-16.1

16.1

Revised beginning balance

300.7

'

'

0.3

286.3

'

'

-64.8

'

'

194.4

-115.5

Net income

47.1

'

'

'

'

'

'

'

'

'

47.1

'

Changes in cumulative translation adjustment

-3.9

'

'

'

'

'

'

'

'

'

'

-3.9

Changes in unrealized gains/(losses) on derivative instruments, net of tax

-0.7

'

'

'

'

'

'

'

'

'

'

-0.7

Treasury stock re-issued

5.7

'

'

'

0.9

'

'

4.8

'

'

'

'

Treasury stock repurchased

-28.1

'

'

'

'

'

'

-28.1

'

'

'

'

Stock option compensation

4.3

'

'

'

4.3

'

'

'

'

'

'

'

Deferred taxes

[1]

-2.6

[2]

'

'

'

'

'

'

'

'

'

'

-2.6

Amortization of prior service credit, net of tax

-0.9

'

'

'

'

'

'

'

'

'

'

-0.9

Amortization of actuarial net losses, net of tax

2

'

'

'

'

'

'

'

'

'

'

2

Actuarial net gains (losses) arising during the year, net of tax

19.5

'

'

'

'

'

'

'

'

'

'

19.5

Ending Balance at Dec. 31, 2011

343.1

'

'

0.3

291.5

'

'

-88.1

'

'

241.5

-102.1

Net income

66.9

'

'

'

'

'

'

'

'

'

66.9

'

Dividend paid

-46.7

'

'

'

'

'

'

'

'

'

-46.7

'

Changes in cumulative translation adjustment

7.2

'

'

'

'

'

'

'

'

'

'

7.2

Changes in unrealized gains/(losses) on derivative instruments, net of tax

-0.1

'

'

'

'

'

'

'

'

'

'

-0.1

Treasury stock re-issued

1

'

'

'

-3.5

'

'

4.5

'

'

'

'

Treasury stock repurchased

-1.4

'

'

'

'

'

'

-1.4

'

'

'

'

Stock option compensation

2.1

'

'

'

2.1

'

'

'

'

'

'

'

Deferred taxes

[2]

0

'

'

'

'

'

'

'

'

'

'

'

Fair value of Strata acquisition-related contingently issuable shares

2

'

'

'

2

'

'

'

'

'

'

'

Amortization of prior service credit, net of tax

-1

'

'

'

'

'

'

'

'

'

'

-1

Amortization of actuarial net losses, net of tax

2.4

'

'

'

'

'

'

'

'

'

'

2.4

Actuarial net gains (losses) arising during the year, net of tax

-58.5

'

'

'

'

'

'

'

'

'

'

-58.5

Ending Balance at Dec. 31, 2012

317

'

'

0.3

292.1

'

'

-85

'

'

261.7

-152.1

Net income

77.8

'

'

'

'

'

'

'

'

'

77.8

'

Dividend paid

-12

'

'

'

'

'

'

'

'

'

-12

'

Changes in cumulative translation adjustment

1.2

'

'

'

'

'

'

'

'

'

'

1.2

Changes in unrealized gains/(losses) on derivative instruments, net of tax

-0.1

'

'

'

'

'

'

'

'

'

'

-0.1

Treasury stock re-issued

4.6

'

'

'

-4.2

'

'

8.8

'

'

'

'

Treasury stock repurchased

-3.7

'

'

'

'

'

'

-3.7

'

'

'

'

Excess tax benefit from stock based payment arrangements

3.8

'

'

'

3.8

'

'

'

'

'

'

'

Stock option compensation

2.5

'

'

'

2.5

'

'

'

'

'

'

'

Deferred taxes

[2]

0

'

'

'

'

'

'

'

'

'

'

'

Fair value of acquisition-related consideration

'

15

6.2

'

'

10.5

4.1

'

4.5

2.1

'

'

Amortization of prior service credit, net of tax

-1

'

'

'

'

'

'

'

'

'

'

-1

Amortization of actuarial net losses, net of tax

4.8

'

'

'

'

'

'

'

'

'

'

4.8

Actuarial net gains (losses) arising during the year, net of tax

-6.7

'

'

'

'

'

'

'

'

'

'

-6.7

Ending Balance at Dec. 31, 2013

$409.40

'

'

$0.30

$308.80

'

'

($73.30)

'

'

$327.50

($153.90)

[1]

Impact on deferred taxes of a change in the associated tax rate on the unrecognized actuarial net losses.

[2]

Impact on deferred taxes during the year ended December 31, 2011 of a change in the associated tax rate on the unrecognized actuarial net losses.

Consolidated_Statements_of_Sto1

Consolidated Statements of Stockholders' Equity (Parenthetical) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Statement Of Stockholders Equity [Abstract]	'	'	'
Dividend paid, per share	$0.50	$2	$0

Nature_of_Operations

Nature of Operations	12 Months Ended
	Dec. 31, 2013
Accounting Policies [Abstract]	'
Nature of Operations	'
	Note 1.    Nature of Operations
	Innospec develops, manufactures, blends, markets and supplies fuel additives, personal care and fragrance products and other specialty chemicals. Our products are sold primarily to oil refineries, personal care and fragrance companies, and other chemical and industrial companies throughout the world. Our fuel additives help improve fuel efficiency, boost engine performance and reduce harmful emissions. Our oilfield specialties business supplies drilling and production chemicals which make exploration and production more cost-efficient, and more environmentally-friendly. Our other specialty chemicals provide effective technology-based solutions for our customers’ processes or products focused in the Personal Care; Polymers; and Fragrance Ingredients markets. Our principal product lines and reportable segments are Fuel Specialties, Performance Chemicals and Octane Additives.
	See Note 3 for financial information on the Company’s reportable segments.

Accounting_Policies

Accounting Policies	12 Months Ended
	Dec. 31, 2013
Accounting Policies [Abstract]	'
Accounting Policies	'
	Note 2.    Accounting Policies
	Revision of Prior Years
	In connection with the preparation of the consolidated financial statements for the fourth quarter of 2013, the Company identified an error in the treatment of the amortization of actuarial net losses. The Company determined that the Market Related Value of Assets (“MRVA”) for Innospec Limited’s United Kingdom Pension Plan has been overstated each year since 2003. The market-related value of plan assets is either fair value if the employer does not defer gains or losses on plan assets, or a calculated value that recognizes changes in fair value in a systematic and rational manner over not more than five years, when the expected long-term rate of return is used to determine net periodic postretirement benefit cost. The overstated MRVA is used to determine the size of “the corridor” under GAAP which has resulted in an understatement of amortization of actuarial net losses within the pension expense each year since 2004. This error affects the non-cash pension expenses in the financial statements for the years ended 2012 and 2011 as reported in this 2013 Form 10-K. For quarterly reporting purposes the whole annual non-cash pension expense adjustment has been reflected in the fourth quarter for each year as the impact on the individual quarters is not considered to be material.
	The Company has applied SEC Staff Accounting Bulletin (SAB) No. 108, Considering the Effects of Prior Year Misstatements when Quantifying Misstatements in Current Year Financial Statements. SAB No. 108 states that registrants must quantify the impact of correcting all misstatements, including both the carryover (iron curtain method) and reversing (rollover method) effects of prior-year misstatements on the current-year financial statements, and by evaluating the error measured under each method in light of quantitative and qualitative factors.
	Under SAB No. 108, prior-year misstatements which, if corrected in the current year would be material to the current year, must be corrected by adjusting prior year financial statements, even though such correction previously was and continues to be immaterial to the prior-year financial statements. Correcting prior-year financial statements for such “immaterial errors” does not require previously filed reports to be amended.
	In accordance with accounting guidance presented in ASC 250-10 (SEC Staff Accounting Bulletin No. 99, Materiality), the Company assessed the materiality of the error and concluded that it was not material to any of the Company’s previously issued financial statements taken as a whole.
	Innospec has calculated the understatement of the non-cash pension expense, net of tax, to be $16.1 million as at 1 January 2011, $1.8 million in 2011 and $1.4 million in 2012. Adjustments have been made as follows:
		Year Ended December 31, 2012
	(in millions)	As			Adjustment			As Revised
		Previously
		Reported
	Selling, general and administrative expenses	$	(117.1	)	$	(1.9	)	$	(119.0	)
	Operating income		98.4			(1.9	)		96.5
	Income before income taxes		95.2			(1.9	)		93.3
	Income taxes		(26.9	)		0.5			(26.4	)
	Net income		68.3			(1.4	)		66.9
	Retained earnings		281			(19.3	)		261.7
	Accumulated other comprehensive loss		(171.4	)		19.3			(152.1	)
		Year Ended December 31, 2011
	(in millions)	As			Adjustment			As Revised
		Previously
		Reported
	Selling, general and administrative expenses	$	(155.9	)	$	(2.4	)	$	(158.3	)
	Operating income		49.6			(2.4	)		47.2
	Income before income taxes		52.6			(2.4	)		50.2
	Income taxes		(3.7	)		0.6			(3.1	)
	Net income		48.9			(1.8	)		47.1
	Retained earnings		259.4			(17.9	)		241.5
	Accumulated other comprehensive loss		(120.0	)		17.9			(102.1	)
		As at January 1, 2011
	(in millions)	As			Adjustment			As Revised
		Previously
		Reported
	Retained earnings	$	210.5		$	(16.1	)	$	194.4
	Accumulated other comprehensive loss		(131.6	)		16.1			(115.5	)
	Basis of preparation: The consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States of America and include all subsidiaries of the Company where the Company has a controlling financial interest. All significant intercompany accounts and balances have been eliminated upon consolidation. All acquisitions are accounted for as purchases and the results of operations of the acquired businesses are included in the consolidated financial statements from the date of acquisition.
	Use of estimates: The preparation of the consolidated financial statements, in accordance with generally accepted accounting principles in the United States of America, requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. Actual results could differ from those estimates.
	Cash equivalents: Investment securities with maturities of three months or less when purchased are considered to be cash equivalents.
	Short-term investments: Investment securities with maturities of more than 3 months and less than 12 months when purchased are considered to be short-term investments.
	Trade and other accounts receivable: The Company records trade and other accounts receivable at net realizable value and maintains allowances for customers not making required payments. The Company determines the adequacy of allowances by periodically evaluating each customer receivable considering our customer’s financial condition, credit history and current economic conditions.
	Inventories: Inventories are stated at the lower of cost (FIFO method) or market value. Cost includes materials, labor and an appropriate proportion of plant overheads. The Company accrues volume discounts where it is probable that the required volume will be attained and the amount can be reasonably estimated. The discounts are recorded as a reduction in the cost of materials based on projected purchases over the period of the agreement. Inventories are adjusted for estimated obsolescence and written down to market value based on estimates of future demand and market conditions.
	Property, plant and equipment: Property, plant and equipment are stated at cost less accumulated depreciation. Depreciation is provided over the estimated useful lives of the assets using the straight-line method and is allocated between cost of goods sold and operating expenses. The cost of additions and improvements are capitalized. Maintenance and repairs are charged to expenses. When assets are sold or retired the associated cost and accumulated depreciation are removed from the consolidated financial statements and any related gain or loss is included in earnings. The estimated useful lives of the major classes of depreciable assets are as follows:
	Buildings		7 to 25 years
	Equipment		3 to 10 years
	Goodwill and other intangible assets: Goodwill and other intangible assets deemed to have indefinite lives are not amortized but are subject to at least annual impairment tests based on projected post-tax cash flows discounted at the Company’s weighted average cost of capital. The annual measurement date for impairment testing of the goodwill relating to the Fuel Specialties and Performance Chemicals segments is December 31. At this date we performed annual impairment tests and concluded that there had been no impairment of goodwill in respect of those reporting segments. The Company capitalizes software development costs, including licenses, subsequent to the establishment of technological feasibility. Other intangible assets deemed to have finite lives, including software development costs and licenses, are amortized using the straight-line method over their estimated useful lives and tested for any potential impairment when events occur or circumstances change which suggest that an impairment may have occurred.
	Deferred finance costs: The costs relating to debt financing are capitalized, separately disclosed in the consolidated balance sheets and amortized using the effective interest method over the expected life of the debt financing facility.
	Impairment of long-lived assets: The Company reviews the carrying value of its long-lived assets, including buildings and equipment, whenever changes in circumstances suggest that the carrying values may be impaired. In order to facilitate this test the Company groups together assets at the lowest possible level for which cash flow information is available. Undiscounted future cash flows expected to result from the assets are compared with the carrying value of the assets and if they are lower an impairment loss may be recognized. The amount of the impairment loss is the difference between the fair value and the carrying value of the assets. Fair values are determined using post-tax cash flows discounted at the Company’s weighted average cost of capital.
	Derivative instruments: The Company uses various derivative instruments including forward currency contracts, options, interest rate swaps and commodity swaps to manage certain exposures. These instruments are entered into under the Company’s corporate risk management policy to minimize exposure and are not for speculative trading purposes. The Company recognizes all derivatives as either non-current assets or liabilities in the consolidated balance sheet and measures those instruments at fair value. Changes in the fair value of derivatives that are not designated as hedges, or do not meet the requirements for hedge accounting, are recognized in earnings. Derivatives which are designated as hedges are tested for effectiveness on a quarterly basis, and marked to market. The ineffective portion of the derivative’s change in value is recognized in earnings. The effective portion is recognized in other comprehensive income until the hedged item is recognized in earnings.
	Environmental compliance and remediation: Environmental compliance costs include ongoing maintenance, monitoring and similar costs. We recognize environmental liabilities when they are probable and costs can be reasonably estimated, and asset retirement obligations when there is a legal obligation and costs can be reasonably estimated. Such accruals are adjusted as further information develops or circumstances change. Costs of future obligations are discounted to their present values using the Company’s credit-adjusted risk-free rate.
	Acquisition-related contingent and deferred consideration: Deferred consideration payable in cash is discounted to its fair value. Where deferred consideration is contingent upon pre-determined financial targets, an estimate of the fair value of the likely consideration payable is made. This contingent deferred consideration is re-assessed annually and a corresponding adjustment is recognized in operating income, and the associated liability, to reflect the passage of time accretion expense and any revisions to the amount or timing of the initial measurement.
	Revenue recognition: The Company supplies products to customers from its various manufacturing sites, and in some instances from containers held on customer sites, under a variety of standard shipping terms and conditions. In each case revenue is recognized when legal title, which is defined and generally accepted in the standard terms and conditions, and risk of loss transfers between the Company and the customer. Provisions for sales discounts and rebates to customers are based upon the terms of sales contracts and are recorded in the same period as the related sales as a deduction from revenue. The Company estimates the provision for sales discounts and rebates based on the terms of each agreement at the time of shipping.
	Components of net sales: All amounts billed to customers relating to shipping and handling are classified as net sales. Shipping and handling costs incurred by the Company are classified as cost of goods sold.
	Components of cost of goods sold: Cost of goods sold is comprised of raw material costs including inbound freight, duty and non-recoverable taxes, inbound handling costs associated with the receipt of raw materials, packaging materials, manufacturing costs including labor costs, maintenance and utility costs, plant and engineering overheads, amortization expense for certain other intangible assets, warehousing and outbound shipping costs and handling costs. Inventory losses and provisions and the costs of customer claims are also recognized in the cost of goods line item.
	Components of selling, general and administrative expenses: Selling expenses comprise the costs of the direct sales force, and the sales management and customer service departments required to support them. It also comprises commission charges, the costs of sales conferences and trade shows, the cost of advertising and promotions, amortization expense for certain other intangible assets, and the cost of bad and doubtful debts. General and administrative expenses comprise the cost of support functions including accounting, human resources, information technology and the cost of group functions including corporate management, finance, tax, treasury, investor relations and legal departments. Provision of management’s best estimate of legal and settlement costs for litigation in which the Company is involved is made and reported in the administrative expense line item.
	Research and development expenses: Research, development and testing costs are expensed to the income statement as incurred.
	Earnings per share: Basic earnings per share is based on the weighted average number of common shares outstanding during the period. Diluted earnings per share includes the effect of options that are dilutive and outstanding during the period.
	Foreign currencies: The Company’s policy is that foreign exchange differences arising on the translation of the balance sheets of entities that have functional currencies other than the U.S. dollar are taken to a separate equity reserve, the cumulative translation adjustment. In entities where the U.S. dollar is the functional currency no gains or losses on translation occur, and gains or losses on monetary assets relating to currencies other than the U.S. dollar are taken to the income statement in other net income/(expense). Other foreign exchange gains or losses are also included in other net income/(expense) in the income statement.
	Share based compensation plans: The Company accounts for employee stock options and stock equivalent units under the fair value method. Stock options are fair valued at the grant date and the fair value is recognized straight-line over the vesting period of the option. Stock equivalent units are fair valued at each balance sheet date and the fair value is spread over the remaining vesting period of the unit.
	Pension plans and other post-employment benefits: The Company recognizes the funded status of defined benefit post-retirement plans on the consolidated balance sheets and changes in the funded status in comprehensive income. The measurement date of the plan’s funded status is the same as the Company’s fiscal year-end. Prior service costs and credits and actuarial gains and losses are amortized over the average remaining life expectancy of the inactive participants using the corridor method.
	Income taxes: The Company provides for income taxes by recognizing deferred tax assets and liabilities for the expected future tax consequences of temporary differences between the financial statement carrying amounts and the relevant tax bases of the assets and liabilities. When appropriate, the Company evaluates the need for a valuation allowance to reduce deferred tax assets. The Company recognizes future tax benefits to the extent that realization of such benefits is more likely than not. The effect on deferred taxes of a change in tax rates is recognized in the period that includes the enactment date. Income tax positions must meet a more likely than not recognition criteria to be recognized. The Company recognizes accrued interest and penalties associated with uncertain tax positions as part of income taxes in our consolidated statements of income.

Segmental_Reporting_and_Geogra

Segmental Reporting and Geographical Area Data	12 Months Ended
	Dec. 31, 2013
Segment Reporting [Abstract]	'
Segmental Reporting and Geographical Area Data	'
	Note 3.    Segmental Reporting and Geographical Area Data
	Innospec divides its business into three segments for management and reporting purposes: Fuel Specialties, Performance Chemicals and Octane Additives. The Fuel Specialties and Performance Chemicals segments operate in markets where we actively seek growth opportunities although their ultimate customers are different. The Octane Additives segment is generally characterized by volatile and declining demand.
	In 2013, the Company had a significant customer in the Fuel Specialties segment, Royal Dutch Shell plc and its affiliates (“Shell”), which accounted for $83.1 million (10%) of our net group sales. In 2012 and 2011, Shell accounted for $82.9 million (11%) and $78.7 million (10%) of our net group sales, respectively.
	The Company evaluates the performance of its segments based on operating income. The following table analyzes sales and other financial information by the Company’s reportable segments:
	(in millions)		2013			2012			2011
	Net sales:
	Fuel Specialties		$	567.4		$	527.2		$	521.2
	Performance Chemicals			192.4			179.6			177
	Octane Additives			59			69.6			76.2
			$	818.8		$	776.4		$	774.4
	Gross profit:
	Fuel Specialties		$	181.1		$	158.7		$	149.3
	Performance Chemicals			46.3			43.8			40.6
	Octane Additives			27.8			33.9			36.5
			$	255.2		$	236.4		$	226.4
	Operating income:
	Fuel Specialties		$	92.7		$	87.6		$	81.7
	Performance Chemicals			23.6			24.3			22.6
	Octane Additives			21.5			26			(22.4	)
	Pension credit/(charge)			(2.3	)		(1.6	)		(2.9	)
	Corporate costs			(43.4	)		(38.5	)		(29.2	)
	Restructuring charge			(0.2	)		(0.2	)		(0.6	)
	Impairment of Octane Additives segment goodwill			(1.3	)		(1.2	)		(2.0	)
	Profit on disposal, net			0			0.1			0
	Total operating income		$	90.6		$	96.5		$	47.2
	Identifiable assets at year end:
	Fuel Specialties		$	446.4		$	356.6		$	281.5
	Performance Chemicals			176.8			113.4			106.7
	Octane Additives			42			48.9			51.5
	Corporate			128.8			60.5			129.1
			$	794		$	579.4		$	568.8
	The pension charge relates to the United Kingdom defined benefit pension plan which is closed to future service accrual. The charges related to our other much smaller pension arrangements in the U.S. and overseas are included in the segment and income statement captions consistent with the related employees’ costs.
	The Company includes within the corporate costs line item the costs of:
		•		managing the Group as a company with securities listed on the NASDAQ and registered with the SEC;
		•		the President/CEO’s office, group finance, group human resources, group legal and compliance counsel, and investor relations;
		•		running the corporate offices in the U.S. and Europe;
		•		the corporate development function since they do not relate to the current trading activities of our other reporting segments; and
		•		the corporate share of the information technology, accounting and human resources departments.
	Sales by geographical area are reported by source (where the transactions originate) and by destination (where the final sales to customers are made). Intercompany sales are priced to recover cost plus an appropriate mark-up for profit and are eliminated in the consolidated financial statements.
	Identifiable assets are those directly associated with the operations of the geographical area.
	Goodwill has not been allocated by geographical location on the grounds that it would be impracticable to do so.
	(in millions)		2013			2012			2011
	Net sales by source:
	United States		$	276.1		$	274.1		$	265.6
	United Kingdom			502.4			475.1			482.8
	Rest of Europe			129.1			142.8			151.7
	Other			0.2			0.5			0.9
	Sales between areas			(89.0	)		(116.1	)		(126.6	)
			$	818.8		$	776.4		$	774.4
	Net sales by destination:
	United States		$	278.7		$	272.4		$	248.2
	United Kingdom			30			38.8			48.5
	Rest of Europe			325.5			331			304.2
	Other			184.6			134.2			173.5
			$	818.8		$	776.4		$	774.4
	Income before income taxes:
	United States		$	10		$	5.6		$	(42.6	)
	United Kingdom			43.7			36.3			36.6
	Rest of Europe			40.4			52.6			58.2
	Impairment of Octane Additives segment goodwill			(1.3	)		(1.2	)		(2.0	)
			$	92.8		$	93.3		$	50.2
	Long-lived assets at year end:
	United States		$	148.2		$	31.5		$	22
United Kingdom			29.4			28.7			32.4
Rest of Europe			11.5			11.5			10.9
		$	189.1		$	71.7		$	65.3
Identifiable assets at year end:
United States		$	291		$	174.1		$	123.2
United Kingdom			261.5			192.1			253.8
Rest of Europe			53.2			63.8			49.8
Other			0.4			0.4			0.5
Goodwill			187.9			149			141.5
		$	794		$	579.4		$	568.8

Earnings_Per_Share

Earnings Per Share	12 Months Ended
	Dec. 31, 2013
Earnings Per Share [Abstract]	'
Earnings Per Share	'
	Note 4.    Earnings Per Share
	Basic earnings per share is based on the weighted average number of common shares outstanding during the period. Diluted earnings per share includes the effect of options that are dilutive and outstanding during the period. Per share amounts are computed as follows:
		2013		2012		2011
	Numerator (in millions):
	Net income available to common stockholders	$	77.8	$	66.9	$	47.1
	Denominator (in thousands):
	Weighted average common shares outstanding		23,651		23,187		23,568
	Dilutive effect of stock options and awards		505		663		952
	Denominator for diluted earnings per share		24,156		23,850		24,520
	Net income per share, basic:	$	3.29	$	2.89	$	2
	Net income per share, diluted:	$	3.22	$	2.81	$	1.92
	In 2013, 2012 and 2011 the average number of anti-dilutive options excluded from the calculation of diluted earnings per share were nil, 1,380 and 690 respectively.

Property_Plant_and_Equipment

Property, Plant and Equipment	12 Months Ended
	Dec. 31, 2013
Property Plant And Equipment [Abstract]	'
Property, Plant and Equipment	'
	Note 5.    Property, Plant and Equipment
	Property, plant and equipment consists of the following:
	(in millions)	2013			2012
	Land	$	7.5		$	7.2
	Buildings		10.8			6.5
	Equipment		152.9			129
	Work in progress		3.9			3.5
			175.1			146.2
	Less accumulated depreciation		(114.7	)		(96.4	)
		$	60.4		$	49.8
	Of the total net book value of equipment at December 31, 2013 and 2012 no amounts are in respect of assets held under capital leases.
	Depreciation charges were $8.9 million, $7.0 million and $9.2 million in 2013, 2012 and 2011, respectively.
	The estimated additional cost to complete work in progress is $2.2 million (2012 – $2.7 million).

Goodwill

Goodwill	12 Months Ended
	Dec. 31, 2013
Goodwill And Intangible Assets Disclosure [Abstract]	'
Goodwill	'
	Note 6.    Goodwill
	The following table analyzes goodwill for 2013 and 2012.
	(in millions)		Fuel			Performance		Octane			Total
			Specialties			Chemicals		Additives
	At January 1, 2012
	Gross cost (1)		$	108.8		$	30.1	$	236.6		$	375.5
	Accumulated impairment losses			0			0		(234.0	)		(234.0	)
	Net book amount			108.8			30.1		2.6			141.5
	Exchange effect			0.1			0		(0.1	)		0
	Acquisitions			8.7			0		0			8.7
	Impairment losses			0			0		(1.2	)		(1.2	)
	At December 31, 2012
	Gross cost (1)			117.6			30.1		236.5			384.2
	Accumulated impairment losses			0			0		(235.2	)		(235.2	)
	Net book amount			117.6			30.1		1.3			149
	Exchange effect			0			0		0			0
	Acquisitions			22.9			16.7		0			39.6
	Adjustments to purchase price allocation			0.6			0		0			0.6
	Impairment losses			0			0		(1.3	)		(1.3	)
	At December 31, 2013
	Gross cost (1)			141.1			46.8		236.5			424.4
	Accumulated impairment losses			0			0		(236.5	)		(236.5	)
	Net book amount		$	141.1		$	46.8	$	0		$	187.9
	-1	Gross cost is net of $8.7 million, $0.3 million and $289.5 million of historical accumulated amortization in respect of the Fuel Specialties, Performance Chemicals and Octane Additives reporting segments, respectively.
	The Company’s reporting units, the level at which goodwill is tested for impairment, are consistent with the reportable segments: Fuel Specialties, Performance Chemicals and Octane Additives. The components in each segment (including products, markets and competitors) have similar economic characteristics and the segments, therefore, reflect the lowest level at which operations and cash flows can be clearly distinguished, operationally and for financial reporting purposes, from the rest of the Company.
	The Company tests goodwill annually for impairment, or between years if events occur or circumstances change which suggests impairment may have occurred. At December 31, 2013, the fair value of our Fuel Specialties and Performance Chemicals segments substantially exceeds the carrying value.
	To determine the fair value of each of our segments we utilize a discounted cash flow methodology based on the forecasted future after-tax cash flows from operations for each since we believe this provides the best approximation of fair value. This methodology requires us to make assumptions and estimates including those in respect of future revenue growth and gross margins, which are based upon our long range plans, and the Company’s weighted average cost of capital. Our long range plans are regularly updated as part of our planning processes and are reviewed and approved by management and our Board of Directors. We assume terminal values for the Fuel Specialties and Performance Chemicals reporting units which are added to the present value of the relevant forecasted future cash flows. We assume no terminal value for the Octane Additives reporting unit beyond its estimated future life. The discounted cash flow methodology does not assume a control premium. We use a discount rate equivalent to the Company’s weighted average cost of capital which is estimated by reference to the overall after-tax rate of return required by equity and debt market participants in the Company. We assign assets and liabilities, including deferred taxes and goodwill, to our reporting units if the asset or liability relates to the operations of that reporting unit and is included in determining the fair value of the reporting unit. Cash and debt obligations are excluded from the carrying value of our reporting units.
	In 2013 some of the assumptions and estimates underpinning our discounted cash flows were revised as part of our planning processes although the methodology was unchanged. The most significant revisions were that the Company’s weighted average cost of capital was changed to reflect the changing proportion of debt to equity funding of the Company.
	The Company elected to perform its annual tests in respect of Fuel Specialties and Performance Chemicals goodwill as at December 31 each year. At December 31, 2013 we had $141.1 million and $46.8 million of goodwill relating to our Fuel Specialties and Performance Chemicals segments, respectively. At this date we performed annual impairment tests and concluded that there had been no impairment of goodwill in respect of those reporting segments.
	As a result of the Octane Additives impairment tests performed during 2013, 2012 and 2011 impairment charges of $1.3 million, $1.2 million and $2.0 million, respectively, have been recognized. These charges are non-cash in nature and have no impact on taxation. At December 31, 2013 to the goodwill in the Octane Additives segment was fully impaired. Remaining sales are concentrated around a relatively small number of customers with a risk that future demand could dramatically decline.
	We believe that the assumptions used in our annual and quarterly impairment tests are reasonable, but that they are judgmental, and variations in any of the assumptions may result in materially different calculations of impairment charges, if any.
	The Bachman Group Companies Acquisition
	On November 4, 2013, the Company acquired 100% of the voting equity interests in Bachman Services, Inc., Specialty Intermediates, Inc., Bachman Production Specialties, Inc. and Bachman Drilling & Production Specialties, Inc. (collectively “Bachman”). Bachman provide chemicals and services to the oil and gas industry and are based in Oklahoma City, Oklahoma. We purchased Bachman for a cash consideration of $45.8 million and by the issuance of 319,953 shares of unregistered Innospec Inc. common stock to the previous owners with a fair value of approximately $15 million, based on the Innospec share price on the closing date. We acquired the businesses in order to move us towards critical mass, and bring both good technology and market positioning in the oilfield specialties sector which forms part of our Fuel Specialties segment.
	Included in the consolidated income statement of the Company since the acquisition date, are the following revenue and earnings for Bachman combined:
	(in millions)		Bachman
	Net sales		$	9.7
	Net income		$	0.3
	The following table summarizes the calculations of the total purchase price and the estimated allocation of the purchase price to the assets acquired and liabilities assumed for Bachman. The purchase price allocation is not yet complete as we are in the process of finalising the valuation of the assets acquired. Final determination of the fair values may result in adjustments to the amounts presented below:
	(in millions)		Bachman
	Other intangible assets		$	25.9
	Goodwill			22.9
	Deferred tax on intangibles			(7.6	)
	Other net assets acquired, excluding cash of $2.0m			17.6
	Purchase price, net of cash acquired		$	58.8
	Bachman, and the associated goodwill, are included within our Fuel Specialties segment for management and reporting purposes (see Note 7 for further information on the other intangible assets).
	Chemsil and Chemtec Acquisitions
	On August 30, 2013, the Company acquired 100% of the voting equity interests in Chemsil Silicones, Inc. (“Chemsil”) and Chemtec Chemical Co. (“Chemtec”), both of which are based at Chatsworth in Los Angeles, California. Chemsil develops and markets silicone-based formulations to the personal care industry and Chemtec distributes a wide range of personal care ingredients. We acquired these businesses in order to add to both the technology base and the geographical footprint of our Personal Care business within our Performance Chemicals segment.
	The purchase price for Chemsil and Chemtec, net of cash acquired, comprised $51.2 million in cash and $6.2 million of Innospec Inc. common stock transferred to the previous owner on the acquisition date.
	Included in the consolidated income statement of the Company since the acquisition date, are the following revenue and earnings for Chemsil and Chemtec combined:
	(in millions)		Chemsil
			&
			Chemtec
	Net sales		$	11.8
	Net income		$	1
	The following table summarizes the calculations of the total purchase price and the allocation of the purchase price to the assets acquired and liabilities assumed for Chemsil and Chemtec, which is now complete:
	(in millions)		Chemsil
			&
			Chemtec
	Other intangible assets		$	34
	Goodwill			16.7
	Other net assets, excluding cash of $1.3m			6.7
	Purchase price, net of cash acquired		$	57.4
	Chemsil and Chemtec, and the associated goodwill, are included within our Performance Chemicals segment for management and reporting purposes (see Note 7 for further information on the other intangible assets).
Supplemental unaudited pro forma information
For illustrative purposes only pro forma information of the enlarged group is provided below but is not necessarily indicative of what the financial position or results of operations would have been had the acquisitions of Strata, Chemsil, Chemtec and Bachman been completed as of January 1, 2012. In addition, the unaudited pro forma financial information is not indicative of, nor does it purport to project, the future financial position of operating results of the enlarged group.
(in millions, except per share data)		2013			2012
Net sales		$	913.1		$	904.6
Net income		$	85.1		$	77.2
Earnings per share – basic		$	3.42		$	3.33
– diluted		$	3.36		$	3.24
Adjustments to the unaudited pro forma financial information includes amortization in respect of the acquired other intangible assets for all acquisitions, and the acquisition-related costs incurred in respect of all these transactions.
Adjustments to Strata purchase price allocation
During 2013, we finalized our calculations of the fair values of assets acquired and liabilities assumed in the acquisition of Strata, resulting in a $0.6 million reduction in other net assets acquired and a corresponding increase in goodwill.

Other_Intangible_Assets

Other Intangible Assets	12 Months Ended
	Dec. 31, 2013
Goodwill And Intangible Assets Disclosure [Abstract]	'
Other Intangible Assets	'
	Note 7.    Other Intangible Assets
	Other intangible assets comprise the following:
	(in millions)	2013			2012
	Gross cost:
	– Product rights	$	34		$	0
	– Brand names		2.9			0
	– Technology		33.9			25.4
	– Customer relationships		58.7			44.2
	– Patents		2.9			2.9
	– Internally developed software and other costs		19.5			10.1
	– Non-compete agreements		1.5			1.5
	– Marketing related		22.1			22.1
			175.5			106.2
	Accumulated amortization:
	– Product rights		(1.3	)		0
	– Brand names		(0.1	)		0
	– Technology		(7.9	)		(6.0	)
	– Customer relationships		(16.8	)		(12.7	)
	– Patents		(2.6	)		(2.3	)
	– Internally developed software and other costs		(1.0	)		0
	– Non-compete agreements		(0.7	)		0
	– Marketing related		(18.3	)		(16.6	)
			(48.7	)		(37.6	)
		$	126.8		$	68.6
	Product rights
	Following the acquisition of Chemsil on August 30, 2013, the Company has recognized an intangible asset of $34.0 million in respect of Chemsil’s product rights portfolio. This asset has an expected life of 9 years and is being amortized on a straight-line basis over this period. An amortization expense of $1.3 million was recognized in 2013 (2012 – $0.0 million) in cost of goods sold. No residual value is anticipated.
	Brand names
	Following the acquisition of Bachman on November 4, 2013, the Company recognized an intangible asset of $2.9 million in respect of Bachman’s brand names. This asset has an expected life of 5 years and is being amortized on a straight-line basis over this period. An amortization expense of $0.1 million was recognized in 2013 (2012 – $0.0 million) in selling, general and administrative expenses. No residual value is anticipated.
	Technology
	Following the acquisition of Bachman on November 4, 2013, the Company recognized an intangible asset of $8.5 million in respect of Bachman’s core chemistry know-how of oilfield chemicals. This asset has an expected life of 15 years and is being amortized on a straight-line basis over this period. No residual value is anticipated.
	Following the acquisition of Strata on December 24, 2012, the Company recognized an intangible asset of $18.3 million in respect of technological know-how of the mixing and manufacturing process, patents which protect the technology and the associated product branding. This asset has an expected life of 16.5 years and is being amortized on a straight-line basis over this period. No residual value is anticipated.
	Following the acquisition of the remaining 50% of Innospec Fuel Specialties LLC on July 8, 2004, the Company recognized an intangible asset of $2.3 million in respect of various technological approvals the business has received from certain military and civilian authorities. The approvals act as a barrier to entry to any potential competitor in the market who would wish to supply these products. This asset has an expected life of 10 years and is being amortized on a straight-line basis over this period. No residual value is anticipated.
	An intangible asset of $4.8 million was recognized in respect of a number of specialized manufacturing processes carried out by Innospec Widnes Limited following the acquisition of that entity in August 2004. This asset has an expected life of 10 years and is being amortized on a straight-line basis over this period. No residual value is anticipated.
	An amortization expense of $1.9 million was recognized in 2013 (2012 – $0.7 million) in cost of goods sold.
	Customer relationships
	Following the acquisition of Bachman on November 4, 2013, the Company recognized an intangible asset of $14.5 million in respect of Bachman’s long-term customer relationships. This asset has a weighted average expected life of 14.5 years and is being amortized on a straight-line basis over this period. No residual value is anticipated.
	Following the acquisition of Strata on December 24, 2012, the Company recognized an intangible asset of $28.2 million in respect of long-term customer relationships. This asset has an expected life of 11.5 years and is being amortized on a straight-line basis over this period. No residual value is anticipated.
	Following the acquisition of Finetex (now merged into Innospec Active Chemicals LLC) in January 2005, the Company recognized an intangible asset totaling $7.1 million, $4.2 million of which was in relation to customer lists acquired. This asset has an expected life of 13 years and is being amortized on a straight-line basis over this period. No residual value is anticipated.
	Intangible assets were recognized in 2004 in respect of both the Innospec Fuel Specialties LLC ($9.0 million) and Innospec Widnes Limited ($2.8 million) acquisitions, and relate to ongoing customer relationships. These assets have an expected life of 10 years and are being amortized on a straight-line basis over this period. No residual value is anticipated.
	An amortization expense of $4.1 million was recognized in 2013 (2012 – $1.5 million) in selling, general and administrative expenses.
	Patents
	Following the acquisition of Finetex, the Company recognized an intangible asset of $2.9 million in respect of patents and trademarks. These have an expected life of 10 years and are being amortized on a straight-line basis over this period. No residual value is anticipated. An amortization expense of $0.3 million was recognized in 2013 (2012 – $0.3 million) in cost of goods sold.
	Internally developed software and other costs
	We are continuing with the implementation of our new, company-wide, information system platform, following the successful deployment at the majority of our U.S. sites in the third quarter of 2013. At December 31, 2013 we had capitalized $19.5 million (2012 – $10.1 million) in relation to this internally developed software. This asset has an expected life of 5 years and is being amortized on a straight-line basis over this period. No residual value is anticipated. An amortization expense of $1.0 million was recognized in 2013 (2012 – $0.0 million) in selling, general and administrative expenses.
	Non-compete agreements
	Following the acquisition of Strata on December 24, 2012, the Company recognized an intangible asset of $1.5 million in respect of a non-compete agreement. This asset has an expected life of 2 years and is being amortized on a straight-line basis over this period. No residual value is anticipated. An amortization expense of $0.7 million was recognized in 2013 (2012 – $0.0 million) in selling, general and administrative expenses.
	Marketing related (formerly Ethyl)
	An intangible asset of $28.4 million was recognized in the second quarter of 2007 in respect of Ethyl Corporation foregoing their entitlement effective April 1, 2007 to a share of the future income stream under the sales and marketing agreements to market and sell TEL. In 2008, contract provisions no longer deemed necessary of $6.3 million were offset against the intangible asset. The amount attributed to the Octane Additives reporting segment was being amortized straight-line to December 31, 2012 and the amount attributed to the Fuel Specialties reporting segment is being amortized straight-line to December 31, 2017. Effective October 1, 2011, the Company extended its estimate for the future life of the Octane Additives segment from December 31, 2012 to December 31, 2013 and therefore prospectively adjusted the amortization period for the amount attributed to the Octane Additives segment. An amortization expense of $1.7 million was recognized in 2013 (2012 – $1.6 million) in cost of goods sold.
	Amortization expense
	The aggregate of other intangible asset amortization expense was $11.1 million, $4.1 million and $4.4 million in 2013, 2012 and 2011, respectively, of which $3.8 million, $2.6 million and $2.9 million, respectively, was recognized in cost of goods sold, and the remainder was recognized in selling, general and administrative expenses.
	Future amortization expense is estimated to be as follows for the next five years:
	(in millions)
	2014	$	16.6
	2015	$	16.6
	2016	$	16.6
	2017	$	16.6
	2018	$	14.3

Deferred_Finance_Costs

Deferred Finance Costs	12 Months Ended
	Dec. 31, 2013
Text Block [Abstract]	'
Deferred Finance Costs	'
	Note 8.     Deferred Finance Costs
	On August 28, 2013, we amended our five-year revolving credit facility (“the facility”). The amendment provides for an increase in the facility available to the Company and certain subsidiaries of the Company from $100 million to $150 million and retains the term of the facility through to December 2016. In addition, the amendment allows the Company to request an additional amount of up to $50 million to be committed by the lenders, of which $30 million was committed in the fourth quarter of 2013. As a result $0.9 million of refinancing costs have been capitalized in 2013 and are being amortized over the expected life of the facility using the effective interest method, in line with the costs capitalized for the original facility in December 2011.
	(in millions)	2013			2012
	Gross cost	$	2.6		$	1.7
	Accumulated amortization		(0.8	)		(0.4	)
		$	1.8		$	1.3
	Amortization expense was $0.4 million, $0.4 million and $0.5 million in 2013, 2012 and 2011, respectively. The charge is included in interest expense (see Note 2).

Pension_Plans

Pension Plans	12 Months Ended
	Dec. 31, 2013
Compensation And Retirement Disclosure [Abstract]	'
Pension Plans	'
	Note 9.     Pension Plans
	United Kingdom plan
	The Company maintains a defined benefit pension plan (the “Plan”) covering a number of its current and former employees in the United Kingdom, although it does also have other much smaller pension arrangements in the U.S. and overseas. The Plan is closed to future service accrual but has a large number of deferred and current pensioners. The Projected Benefit Obligation (“PBO”) is based on final salary and years of credited service reduced by social security benefits according to a plan formula. Normal retirement age is 65 but provisions are made for early retirement. The Plan’s assets are invested by several investment management companies in funds holding United Kingdom and overseas equities, United Kingdom and overseas fixed interest securities, index linked securities, property unit trusts and cash or cash equivalents. The trustees’ investment policy is to seek to achieve specified objectives through investing in a suitable mixture of real and monetary assets. The trustees recognize that the returns on real assets, while expected to be greater over the long-term than those on monetary assets, are likely to be more volatile. A mixture across asset classes should nevertheless provide the level of returns required by the Plan to meet its liabilities at an acceptable level of risk for the trustees and an acceptable level of cost to the Company.
	During the second quarter of 2010 the Company implemented a pension increase exchange (“PIE”) program for current pensioners, effective April 1, 2010, which reduced the PBO by $17.1 million. This reduction in PBO resulted in a prior service credit which is being amortized using the straight-line method over the remaining life expectancy of Plan pensioners of 15 years commencing April 1, 2010.
	When the plan closed to future accrual in 2010 all employees became inactive and GAAP requires that the average remaining life expectancy of the inactive participants is used, instead of the average remaining service, to spread future amortization of actuarial net losses. The average remaining life expectancy of the inactive participants has been approximately 24 years since the plan closed in 2010.
	In 2013, the Company contributed approximately $11 million in cash to the Plan in accordance with an actuarial deficit recovery plan agreed with the trustees.
	(in millions)	2013			2012			2011
	Plan net pension charge/(credit):
	Service cost	$	1.6		$	1.6		$	1.6
	Interest cost on PBO		31.3			32.2			36.6
	Expected return on plan assets		(35.5	)		(34.1	)		(36.7	)
	Amortization of prior service credit		(1.3	)		(1.3	)		(1.3	)
	Amortization of actuarial net losses		6.2			3.2			2.7
		$	2.3		$	1.6		$	2.9
	Plan assumptions at December 31, (%):
	Discount rate		4.4			4.15			4.75
	Inflation rate		2.55			2.2			2.15
	Rate of return on plan assets – overall on bid-value		4.85			4.9			4.85
	Rate of return on plan assets – equity securities		7.5			7.25			7.7
	Rate of return on plan assets – debt securities		3.4			3.65			3.6
	Plan asset allocation by category (%):
	Equity securities		35			33			29
	Debt securities		61			61			66
	Cash		4			6			5
			100			100			100
	The discount rate used represents the annualized yield based on a cash flow matched methodology with reference to an AA corporate bond spot curve and having regard to the duration of the Plan’s liabilities. The inflation rate is derived using a similar cash flow matched methodology as used for the discount rate but having regard to the difference between yields on fixed interest and index linked United Kingdom government gilts. The rate of increase in compensation levels is no longer relevant since the Company closed the Plan to future service accrual with effect from March 31, 2010. A 0.25% change in the discount rate assumption would change the PBO by approximately $28 million and the net pension charge for 2014 by approximately $0.5 million. A 0.25% change in the level of price inflation assumption would change the PBO by approximately $22 million and the net pension charge for 2014 by approximately $1.7 million.
	The current investment strategy of the Plan is to obtain an asset allocation of 65% debt securities and 35% equity securities in order to achieve a more predictable return on assets. As at December 31, 2013 and 2012, approximately 55% of the Plan’s assets were held in index-tracking funds with one investment management company. Approximately 25% of the Plan’s assets were invested in United Kingdom government gilts. No more than 5% of the Plan’s assets were invested in any one individual company’s investment funds.
	Movements in PBO and fair value of Plan assets are as follows:
	(in millions)	2013			2012
	Change in PBO:
	Opening balance	$	805.3		$	687.4
	Interest cost		31.3			32.2
	Service cost		1.6			1.6
	Benefits paid		(39.4	)		(43.9	)
	Actuarial losses/(gains)		5.9			94.4
	Exchange effect		15.1			33.6
	Closing balance	$	819.8		$	805.3
	Fair value of plan assets:
	Opening balance	$	768.6		$	708.8
	Actual benefits paid		(39.4	)		(43.9	)
	Actual contributions by employer		10.8			9.2
	Actual return on assets		35.5			61.2
	Exchange effect		14.8			33.3
	Closing balance	$	790.3		$	768.6
	The accumulated benefit obligation for the Plan was $819.8 million and $805.3 million at December 31, 2013 and 2012, respectively.
	For the vast majority of assets, a market approach is adopted to assess the fair value of the assets, with the inputs being the quoted market prices for the actual securities held in the relevant fund. For Level 3 assets where there is no ready market and for which no indicative dealer prices are available, fund assets are independently evaluated, with the use of agreed upon procedures conducted by an audit firm to provide independent confirmation that proper valuation procedures are being followed. The fair values of pension assets by level of input were as follows:
	(in millions)	Quoted Prices			Significant			Significant			Total
		in Active			Other			Unobservable
		Markets for			Observable			Inputs
		Identical Assets			Inputs			(Level 3)
		(Level 1)			(Level 2)
	At December 31, 2013
	Fixed income securities:
	Debt securities issued by U.S. government and government agencies	$	1.3		$			$			$	1.3
	Debt securities issued by non-U.S. governments and government agencies		198.7									198.7
	Corporate debt securities		275.5									275.5
	Residential mortgage-backed securities		0.2									0.2
	Other asset-backed securities		3.8									3.8
	Equity securities:
	Equity securities held for proprietary investment purposes		156.7									156.7
	Real estate		61.4									61.4
	Other assets					25.3			38.3			63.6
	Total assets at fair value		697.6			25.3			38.3			761.2
Cash		29.1									29.1
Total plan assets	$	726.7		$	25.3		$	38.3		$	790.3
At December 31, 2012
Fixed income securities:
Debt securities issued by U.S. government and government agencies	$	1.6		$			$			$	1.6
Debt securities issued by non-U.S. governments and government agencies		191.3									191.3
Corporate debt securities		284.6									284.6
Residential mortgage-backed securities		0.2									0.2
Other asset-backed securities		3.1									3.1
Equity securities:
Equity securities held for proprietary investment purposes		134.8									134.8
Real estate		33.2									33.2
Other assets					39			31			70
Total assets at fair value		648.8			39			31			718.8
Cash		49.8									49.8
Total plan assets	$	698.6		$	39		$	31		$	768.6
The reconciliation of the fair value of the Plan assets using significant unobservable inputs (Level 3) was as follows:
(in millions)	Other
	Assets
Balance at December 31, 2011	$	28.1
Realized/unrealized gains/(losses):
Relating to assets still held at the reporting date		1.3
Relating to assets sold during the period		0
Purchases, issuances and settlements		0.5
Exchange effect		1.1
Balance at December 31, 2012		31
Realized/unrealized gains/(losses):
Relating to assets still held at the reporting date		3.5
Relating to assets sold during the period		0
Purchases, issuances and settlements		3.6
Exchange effect		0.2
Balance at December 31, 2013	$	38.3
The projected net pension charge for the year ending December 31, 2014 is as follows:
(in millions)
Service cost	$	1.7
Interest cost on PBO		34.7
Expected return on plan assets		(37.3	)
Amortization of prior service credit		(1.3	)
Amortization of actuarial net losses		5.5
	$	3.3
The following benefit payments are expected to be made:
(in millions)
2014	$	49.7
2015	$	47
2016	$	47.9
2017	$	48.5
2018	$	49.2
2019 – 2023	$	258
German plan
The Company also maintains an unfunded defined benefit pension plan covering a number of its current and former employees in Germany (the “German plan”). The German plan is closed to new entrants and has no assets.
(in millions)	2013			2012			2011
German plan net pension charge:
Service cost	$	0.2		$	0.1		$	0.2
Interest cost on PBO		0.3			0.3			0.3
Amortization of prior service cost/(credit)		(0.1	)		0			0
Amortization of actuarial net loss/(gain)		0.2			0			0
	$	0.6		$	0.4		$	0.5
German plan assumptions (%):
Discount rate		3.5			3.25			5
Inflation rate		2			2			2
Rate of increase in compensation levels		2.75			2.75			2.75
Movements in PBO of the German plan are as follows:
(in millions)	2013			2012
Change in PBO:
Opening balance	$	9.3		$	6.3
Service cost		0.2			0.1
Interest cost		0.3			0.3
Amortization of prior service cost/(credit)		(0.1	)		0
Benefits paid		(0.2	)		(0.2	)
Actuarial losses/(gains)		(0.4	)		2.6
Exchange effect		0.5			0.2
Closing balance	$	9.6		$	9.3
The amount of unrecognized actuarial net losses in other comprehensive loss in respect of the German plan is $1.6 million, net of tax of $0.6 million.
Other plans
Company contributions to defined contribution schemes during 2013 were $7.7 million (2012 – $7.4 million).

Income_Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2013
Income Tax Disclosure [Abstract]	'
Income Taxes	'
	Note 10.     Income Taxes
	A roll-forward of unrecognized tax benefits and associated accrued interest and penalties is as follows:
	(in millions)	Interest and			Unrecognized			Total
		Penalties			Tax Benefits
	Opening balance at January 1, 2011	$	0.3		$	8.3		$	8.6
	Additions related to tax positions taken in the current period		0			5.2			5.2
	Additions for tax positions of prior periods		0.2			0.5			0.7
	Reductions for tax positions of prior periods		(0.1	)		(1.8	)		(1.9	)
	Closing balance at December 31, 2011		0.4			12.2			12.6
	Current		(0.3	)		(2.9	)		(3.2	)
	Non-current	$	0.1		$	9.3		$	9.4
	Opening balance at January 1, 2012	$	0.4		$	12.2		$	12.6
	Additions related to tax positions taken in the current period		0			0.2			0.2
	Additions for tax positions of prior periods		0.2			0			0.2
	Reductions due to lapsed statutes of limitations		0			(0.2	)		(0.2	)
	Closing balance at December 31, 2012		0.6			12.2			12.8
	Current		(0.3	)		(2.7	)		(3.0	)
	Non-current	$	0.3		$	9.5		$	9.8
	Opening balance at January 1, 2013	$	0.6		$	12.2		$	12.8
	Additions for tax positions of prior periods		0.6			0.2			0.8
	Reductions due to lapsed statutes of limitations		(0.1	)		(0.5	)		(0.6	)
	Closing balance at December 31, 2013		1.1			11.9			13
	Current		(0.6	)		(6.2	)		(6.8	)
	Non-current	$	0.5		$	5.7		$	6.2
	All of the $13.0 million of unrecognized tax benefits, and interest and penalties, would impact our effective tax rate if recognized.
	We recognize accrued interest and penalties associated with uncertain tax positions as part of income taxes in our consolidated statements of income.
	During the fourth quarter of 2013, the Company recorded a $0.2 million addition to unrecognized tax benefits and there was a $0.5 million reduction in unrecognized tax benefits due to the expiration of applicable statutes of limitations during the first quarter of 2013.
	The Company or one of its subsidiaries files income tax returns with the U.S. federal government, and various state and foreign jurisdictions. As at December 31, 2013 the Company and its U.S. subsidiaries were subject to a federal income tax examination by the IRS for 2009 and an employment tax examination for 2010 and 2011. The Company and its U.S. subsidiaries remain open to federal income tax examination by the IRS for years 2009 onwards. The Company does not currently anticipate that adjustments, if any, arising out of this tax audit would result in a material change to its financial position as at December 31, 2013. The Company’s subsidiaries in foreign tax jurisdictions are open to examination including France (2012 onwards), Germany (2010 onwards), Switzerland (2012 onwards) and the United Kingdom (2011 onwards).
	The sources of income before income taxes were as follows:
	(in millions)	2013			2012			2011
	Domestic	$	10		$	5.6		$	(42.6	)
	Foreign		82.8			87.7			92.8
		$	92.8		$	93.3		$	50.2
	The components of income tax charges are summarized as follows:
	(in millions)	2013			2012			2011
	Current:
	Federal	$	1.6		$	2.9		$	5.4
	Foreign		6.8			11.8			13.6
			8.4			14.7			19
	Deferred:
	Federal		1.8			12.3			(12.8	)
	Foreign		4.8			(0.6	)		(3.1	)
			6.6			11.7			(15.9	)
		$	15		$	26.4		$	3.1
	Cash payments for income taxes were $21.1 million, $13.1 million and $18.1 million during 2013, 2012 and 2011, respectively.
	The effective tax rate varies from the U.S. federal statutory rate because of the factors indicated below:
		2013			2012			2011
	Statutory rate		35	%		35	%		35	%
	Foreign income inclusions		6.1			48.9			20.5
	Impairment of Octane Additives segment goodwill		0.5			0.5			1.3
	Foreign tax credits		(1.9	)		(38.3	)		(25.8	)
	Pension (credit)/charge		(0.3	)		(0.3	)		(9.7	)
	Foreign tax rate differential		(14.6	)		(16.4	)		(19.1	)
	Permanent tax adjustments		(2.5	)		(0.2	)		0.3
	Amortization		1.1			0.5			0.7
	Tax (credit)/charge from previous years		(2.9	)		(0.6	)		(1.9	)
	Net charge/(credit) from unrecognized tax benefits		0.2			0.3			7.7
	United Kingdom income tax rate reduction		0.9			(0.6	)		(4.8	)
	Other items and adjustments, net		(5.4	)		(0.5	)		2
			16.2	%		28.3	%		6.2	%
	Significant factors affecting the variation to statutory rate are set out above and include foreign income inclusions net of foreign tax credits. The mix of taxable profits generated in the different geographical localities in which the Group operates had a significant positive impact on the effective tax rate in 2013.
	Details of deferred tax assets and liabilities are analyzed as follows:
	(in millions)	2013			2012
Deferred tax assets:
Foreign tax credits	$	4.5		$	5.5
Accrued expenses		3.4			4.6
Stock options		5.2			5.5
Excess of tax over book basis in property, plant and equipment		0.9			1.1
Net operating loss carry forwards		0.3			0.3
Pension liabilities		6.5			9.2
Other intangible assets		1			0
Other		3.9			4.7
Valuation allowance		0			0
Deferred tax liabilities:
Goodwill amortization		(7.2	)		(6.9	)
Other intangible assets		(0.3	)		(0.9	)
Excess of book over tax basis in tax deductible goodwill		(0.2	)		0
Excess of book over tax basis in intangible assets		(7.5	)		0
Other		(2.9	)		(3.2	)
Total net deferred tax asset	$	7.6		$	19.9
Deferred taxes are included within the consolidated balance sheets as follows:
Deferred tax assets	$	17.3		$	23.7
Deferred tax liabilities		(9.7	)		(3.8	)
	$	7.6		$	19.9
Current portion of deferred tax assets	$	8.7		$	11
Deferred tax assets, net of current portion		8.6			12.7
Current portion of deferred tax liabilities		(0.2	)		(0.2	)
Deferred tax liabilities, net of current portion		(9.5	)		(3.6	)
	$	7.6		$	19.9
Details of the deferred tax asset valuation allowance are as follows:
(in millions)	2013			2012			2011
At January 1	$	0		$	(7.5	)	$	(10.8	)
Change in foreign tax credits		0			7.5			3.3
At December 31	$	0		$	0		$	(7.5	)
As a result of the Company’s assessment of its net deferred tax assets at December 31, 2013, the Company considers it more likely than not that no valuation allowance is required for $0.3 million (2012 – $0.3 million) of its net operating loss carry forwards and that no valuation allowance is required against its foreign tax credit carry forwards (2012 – $0.0 million).
The net operating loss carry forwards arose in the U.S. in the prior periods as a result of state tax losses. It is expected that sufficient taxable profits will be generated against which these net operating loss carry forwards can be relieved prior to their expiration in 2021. The foreign tax credit carry forwards arose in the U.S. in prior periods. The Company has determined that future foreign income inclusions will be sufficient to utilize all of the $4.5 million (2012 – $5.5 million) of the foreign tax credit carry forwards prior to their expiration in 2017 and 2021 and therefore no valuation allowance is required.
Should it be determined in the future that it is no longer more likely than not that these assets will be realized, a valuation allowance would be required, and the Company’s operating results would be adversely affected during the period in which such a determination would be made.
The Company is in a position to control whether or not to repatriate foreign earnings and we intend to permanently reinvest earnings overseas to fund overseas subsidiaries. No taxes have been provided for the unremitted earnings of our overseas subsidiaries as any tax basis differences relating to investments in these overseas subsidiaries are considered to be permanent in duration. The amount of unremitted earnings at December 31, 2013 and 2012 was approximately $605 million and $717 million, respectively. If these earnings are remitted, additional taxes could result after offsetting foreign income taxes paid although the calculation of the additional taxes is not practical at this time.

LongTerm_Debt

Long-Term Debt	12 Months Ended
	Dec. 31, 2013
Debt Disclosure [Abstract]	'
Long-Term Debt	'
	Note 11.    Long-Term Debt
	Long-term debt consists of the following:
	(in millions)	2013			2012
	Revolving credit facility	$	142		$	20
	Promissory note		5			10
	Other long-term debt		1			0
			148			30
	Less current portion		(5.3	)		(5.0	)
		$	142.7		$	25
	On December 14, 2011, we entered into a five-year revolving credit facility which provides for borrowings by us of up to $100 million. The facility carries an interest rate based on U.S. dollar LIBOR plus a margin of between 1.50% and 2.25% which is dependent on the Company’s ratio of net debt to EBITDA. EBITDA is a non-GAAP measure of liquidity defined in the credit facility. The facility can be drawn down until it expires on December 14, 2016. We repaid the previous finance facility, which was due to expire on February 6, 2012, upon entering into the new credit facility.
	On August 28, 2013, we amended our existing five-year revolving credit facility (“the facility”). The amendment provides for an increase in the facility available to the Company and certain subsidiaries of the Company from $100 million to $150 million and retains the term and conditions of the original facility through to December 2016. In addition, an amendment allowed the Company to request an additional amount of $50 million to be committed by the lenders, of which $30 million was committed in the fourth quarter of 2013.
	The Company’s credit facility contains restrictive clauses which may constrain our activities and limit our operational and financial flexibility. The facility obliges the lenders to comply with a request for utilization of finance unless there is an event of default outstanding. Events of default are defined in the credit facility and include a material adverse change to our assets, operations or financial condition. The facility contains a number of restrictions that limit our ability, amongst other things, and subject to certain limited exceptions, to incur additional indebtedness, pledge our assets as security, guarantee obligations of third parties, make investments, undergo a merger or consolidation, dispose of assets, or materially change our line of business.
	In addition, the credit facility contains terms which, if breached, would result in it becoming repayable on demand. It requires, among other matters, compliance with the following financial covenant ratios measured on a quarterly basis: (1) the ratio of net debt to EBITDA shall not be greater than 2.5:1 and (2) the ratio of EBITDA to net interest shall not be less than 4.0:1. Management has determined that the Company has not breached these covenants throughout the period to December 31, 2013 and expects to not breach these covenants for the next 12 months. The credit facility is secured by a number of fixed and floating charges over certain assets which include key operating sites of the Company and its subsidiaries.
	On September 13, 2011, the Company settled the NewMarket Corporation civil complaint. The settlement agreement included the Company issuing a $15.0 million promissory note to NewMarket Corporation payable in three equal annual installments (carrying simple interest at 1% per annum), the first installment of which was paid on September 7, 2012.
	The weighted average rate of interest on borrowings was 1.6% at December 31, 2013 and 1.6% at December 31, 2012. Payments of interest on long-term debt were $1.0 million, $0.5 million and $1.8 million in 2013, 2012 and 2011, respectively.
	The net cash outflows in respect of refinancing costs were $0.9 million, $0.0 million and $1.7 million in 2013, 2012 and 2011, respectively.

Plant_Closure_Provisions

Plant Closure Provisions	12 Months Ended
	Dec. 31, 2013
Restructuring And Related Activities [Abstract]	'
Plant Closure Provisions	'
	Note 12.    Plant Closure Provisions
	The principal site giving rise to environmental remediation liabilities is the manufacturing site at Ellesmere Port in the United Kingdom, which management believes is the last ongoing manufacturer of TEL. There are also environmental remediation liabilities on a much smaller scale in respect of our other manufacturing sites in the U.S. and Europe. The liability for estimated closure costs of Innospec’s manufacturing facilities includes costs for decontamination and environmental remediation activities (remediation) when demand for TEL diminishes. Severance provisions have been made in relation to Corporate personnel and personnel in each of the three reporting segments.
	Movements in the provisions are summarized as follows:
	(in millions)	Severance			Other			Remediation			Total
					Restructuring
	Total at January 1, 2011	$	1.5		$	0.1		$	25.9		$	27.5
	Charge for the period		0.7			(0.1	)		4.5			5.1
	Utilized in the period		(0.7	)		0			(3.1	)		(3.8	)
	Exchange effect		0			0			(0.2	)		(0.2	)
	Total at December 31, 2011		1.5			0			27.1			28.6
	Due within one year		(0.5	)		0			(3.6	)		(4.1	)
	Due after one year	$	1		$	0		$	23.5		$	24.5
	Total at January 1, 2012	$	1.5		$	0		$	27.1		$	28.6
	Charge for the period		0.2			0			4			4.2
	Utilized in the period		(0.6	)		0			(2.1	)		(2.7	)
	Exchange effect		0			0			0.3			0.3
	Total at December 31, 2012		1.1			0			29.3			30.4
	Due within one year		(0.1	)		0			(5.0	)		(5.1	)
	Due after one year	$	1		$	0		$	24.3		$	25.3
	Total at January 1, 2013	$	1.1			0			29.3			30.4
	Charge for the period		0			0			3.9			3.9
	Utilized in the period		(0.1	)		0			(1.9	)		(2.0	)
	Exchange effect		0			0			0.1			0.1
	Total at December 31, 2013		1			0			31.4			32.4
	Due within one year		0			0			(6.2	)		(6.2	)
	Due after one year	$	1		$	0		$	25.2		$	26.2
	Amounts due within one year refer to provisions where expenditure is expected to arise within one year of the balance sheet date. Severance charges are recognized in the income statement as restructuring costs along with other restructuring costs. Remediation costs are recognized in cost of goods sold.
	Remediation
	The remediation provision represents the Company’s liability for environmental liabilities and asset retirement obligations. The charge for the period in 2013 represents the accretion expense recognized of $2.6 million and a further $1.3 million primarily in respect of changes in the expected cost and scope of future remediation activities. A discount rate of 8.92% was used in valuing the remediation provision.
	We recognize environmental liabilities when they are probable and costs can be reasonably estimated, and asset retirement obligations when there is a legal obligation and costs can be reasonably estimated. The Company has to anticipate the program of work required and the associated future expected costs, and comply with environmental legislation in the countries in which it operates or has operated in. The Company views the costs of vacating our Ellesmere Port site as contingent upon if and when it vacates the site because there is no present intention to do so. The Company has further determined that, due to the uncertain product life of TEL particularly in the market for aviation gasoline and other products being manufactured on the site, there are uncertainties as to the probability and timing of the expected costs. Such uncertainties have been considered in estimating the provision.
	Remediation expenditure utilized provisions of $1.9 million, $2.1 million and $3.1 million in 2013, 2012 and 2011, respectively.

Deferred_Income

Deferred Income	12 Months Ended
	Dec. 31, 2013
Revenue Recognition [Abstract]	'
Deferred Income	'
	Note 13.    Deferred Income
	Deferred income consists of:
	(in millions)	2013			2012
	Deferred income	$	1.5		$	2.3
	Less current portion		(0.3	)		(1.4	)
	Non-current deferred income	$	1.2		$	0.9
	Non-current deferred income of $1.2 million relates to post acquisition government grants received by Innospec Leuna GmbH.

Profit_on_Disposal_Net

Profit on Disposal, Net	12 Months Ended
	Dec. 31, 2013
Other Income And Expenses [Abstract]	'
Profit on Disposal, Net	'
	Note 14.    Profit on Disposal, net
	(in millions)	2013		2012		2011
	Profit on disposal of surplus United Kingdom real estate	$	0	$	0.1	$	0
	Loss on disposal of surplus U.S. real estate		0		0		0
		$	0	$	0.1	$	0
	In the third quarter of 2012, the Company recognized a $0.1 million profit following the disposal of surplus real estate.

Fair_Value_Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2013
Fair Value Disclosures [Abstract]	'
Fair Value Measurements	'
	Note 15.    Fair Value Measurements
	Fair value is the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date (exit price). The Company utilizes a mid-market pricing convention for valuing the majority of its assets and liabilities measured and reported at fair value. The Company utilizes market data or assumptions that market participants would use in pricing the asset or liability, including assumptions about risk and the risks inherent in the inputs to the valuation technique. These inputs can be readily observable, market corroborated or generally unobservable. The Company primarily applies the market approach for recurring fair value measurements and endeavors to utilize the best available information. Accordingly, the Company utilizes valuation techniques that maximize the use of observable inputs and minimize the use of unobservable inputs. The Company is able to classify fair value balances based on the observability of those inputs. The Company gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurement) and the lowest priority to unobservable inputs (Level 3 measurement). Financial assets and liabilities are classified in their entirety based on the lowest level of input that is significant to the fair value measurement. The Company’s assessment of the significance of a particular input to the fair value measurement requires judgment and may affect the valuation of fair value assets and liabilities and their placement within the fair value hierarchy Levels. In 2013, the Company evaluated the fair value hierarchy levels assigned to its assets and liabilities, and concluded that there should be no transfers into or out of Levels 1, 2 and 3.
	The following table presents the carrying amount and fair values of the Company’s assets and liabilities measured on a recurring basis:
		December 31,					December 31,
		2013					2012
	(in millions)	Carrying			Fair		Carrying		Fair
		Amount			Value		Amount		Value
	Assets
	Non-derivatives:
	Cash and cash equivalents	$	80.2		$	80.2	$	22.4	$	22.4
	Short-term investments		6.6			6.6		5.1		5.1
	Non-financial assets (Level 3 measurement):
	Goodwill – Octane Additives		0			0		1.3		1.3
	Derivatives (Level 1 measurement):
	Other non-current assets:
	Commodity swaps		0			0		0.1		0.1
	Foreign currency forward exchange contracts		1			1		0.8		0.8
	Liabilities
	Non-derivatives:
	Long-term debt (including current portion)	$	148		$	148	$	30	$	30
	Non-financial liabilities (Level 3 measurement):
	Stock equivalent units		12.1			12.1		12.6		12.6
	Acquisition-related contingent consideration		4.6			4.6		4.3		4.3
	The following methods and assumptions were used to estimate the fair values of financial instruments:
	Cash and cash equivalents, and short-term investments: The carrying amount approximates fair value because of the short-term maturities of such instruments.
	Long-term debt: Long-term debt principally comprises the revolving credit facility and the promissory note, which were entered into in December 2011 and September 2011, respectively. The carrying amount of long-term debt approximates to the fair value.
	Acquisition-related contingent consideration: Deferred consideration payable in cash is discounted to its fair value. Where deferred consideration is contingent upon pre-determined financial targets, an estimate of the fair value of the likely consideration payable is made.
	Derivatives: The fair value of derivatives relating to interest rate swaps, foreign currency forward exchange contracts and commodity swaps are derived from current settlement prices and comparable contracts using current assumptions.
	Stock equivalent units: The fair values of stock equivalent units are calculated at each balance sheet date using either the Black-Scholes or Monte Carlo method.
	The cumulative gains and losses on the interest rate swaps and commodity swaps are summarized as follows:
	(in millions)	2013			2012
	Balance at January 1	$	0.1		$	0.1
	Change in fair value		(0.1	)		0
	Balance at December 31	$	0		$	0.1
	The commodity swaps are used to manage the Company’s cash flow exposure to raw material cost volatility. They were designated as cash flow hedges and qualified for hedge accounting throughout the year ended December 31, 2011. At March 31, 2012, the commodity hedges were determined to be ineffective and consequently a gain of $0.1 million was recognized in earnings. At December 31, 2011, the commodity hedges were determined to be effective and consequently an unrealized gain of $0.2 million was recorded in other comprehensive income.
	Foreign currency forward exchange contracts primarily relate to contracts entered into to hedge future known transactions or hedge balance sheet net cash positions. The movements in the carrying amounts and fair values of these contracts are largely due to changes in exchange rates against the U.S. dollar.

Derivative_Instruments_and_Ris

Derivative Instruments and Risk Management

12 Months Ended

Dec. 31, 2013

Derivative Instruments And Hedging Activities Disclosure [Abstract]

'

Derivative Instruments and Risk Management

'

Note 16.    Derivative Instruments and Risk Management

The Company has limited involvement with derivative instruments and does not trade them. The Company does use derivatives to manage certain interest rate, foreign currency exchange rate and raw material cost exposures.

As at December 31, 2013 and 2012 the Company had no interest rate instruments designated as effective hedges. The interest rate swaps which expired on February 6, 2012 were ineffective at December 31, 2011 because the Company’s previous finance facility, which carried the corresponding floating rate debt obligations, had been repaid. Accordingly, a loss of $0.1 million was recognized in earnings in 2011.

The Company has hedged the cost of certain raw materials with commodity swaps which are summarized as follows:

December 31,

December 31,

2013

2012

(in millions)

Carrying

Fair

Carrying

Fair

Amount

Value

Amount

Value

Notional quantity – 275 tonnes

$

0.1

$

0.1

Notional quantity – 0 tonnes

$

0

$

0

We enter into various foreign currency forward exchange contracts which are intended to minimize currency exchange rate exposure from expected future cash flows. The contracts have maturity dates of up to four years at the date of inception. These foreign currency forward exchange contracts have not been designated as hedging instruments, and their impact on the income statement in 2013, 2012 and 2011 is summarized below:

Location of Gain/(Loss)

Amount of Gain/(Loss)

Recognized in Income

Recognized in Income

(in millions)

2013

2012

2011

Foreign currency forward exchange contracts

Other income/(expense)

$

(1.5

)

$

1.2

$

1.3

The Company sells a range of Fuel Specialties, Performance Chemicals and Octane Additives to major oil refineries and chemical companies throughout the world. Credit limits, ongoing credit evaluation and account monitoring procedures are intended to minimize bad debt risk. Collateral is not generally required.

Commitments_and_Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2013
Commitments And Contingencies Disclosure [Abstract]	'
Commitments and Contingencies	'
	Note 17.    Commitments and Contingencies
	Operating leases
	The Company has commitments under operating leases primarily for office space, motor vehicles and various items of computer and office equipment. The leases are expected to be renewed and replaced in the normal course of business. Rental expense was $3.1 million in 2013, $2.9 million in 2012 and $2.6 million in 2011. Future commitments under non-cancelable operating leases are as follows:
	(in millions)
	2014	$	2.7
	2015		2.6
	2016		2.3
	2017		1.9
	2018		1.7
	Thereafter		2.9
		$	14.1
	Environmental remediation obligations
	Commitments in respect of environmental remediation obligations are disclosed in Note 12.
	Contingencies
	Resolution of certain government investigations and other matters
	As we have previously disclosed, in the first quarter of 2010, the Company reached a $40.2 million settlement to resolve all matters in respect of investigations by U.S. and United Kingdom government authorities into certain legacy transactions conducted by the Company and its subsidiaries under the United Nations Oil for Food Program (“OFFP”), the U.S. Foreign Corrupt Practices Act (“FCPA”), the U.S. Cuban Assets Control Regulations (“CACR”) and United Kingdom anti-bribery laws. The settlement consists of fines, penalties and disgorgements which are payable over a period of four years commencing 2010. As at December 31, 2013, the expected schedule of payments was as follows:
	(in millions)	Government			Compliance			Total
		Authorities			Monitor
	Fines, penalties and disgorgements	$	40.2		$	0		$	40.2
	Fees and associated expenses		0			3.9			3.9
	Less discounting to fair value		0			0			0
			40.2			3.9			44.1
	Amounts paid		(40.2	)		(3.6	)		(43.8	)
	Exchange effect		0			0			0
			0			0.3			0.3
	Due within one year		0			(0.3	)		(0.3	)
		$	0		$	0		$	0
	For accounting purposes only, we are required under GAAP, in accordance with our accounting policy, to discount elements of the fines, penalties and disgorgements to their fair value.
	Jalal Bezee Mejel Al-Gaood & Partner litigation
	On September 19, 2012, a claim was filed in the High Court of Justice in the United Kingdom by Jalal Bezee Mejel Al-Gaood & Partner and Future Agencies Company Limited (collectively “JAG”) against the Company, Innospec Limited and a former employee of Innospec Limited. The Company believes JAG was the former Iraq distributor for Afton Chemicals Limited, a subsidiary of NewMarket Corporation, from at least 2005 until termination of that relationship in 2010. The stated claim, inclusive of costs and expenses, is for up to $42.3 million and relates to alleged loss of profits for JAG’s business in Iraq between 2004 and 2010. The Company believes that the allegations in the JAG claim are without merit and intends to defend vigorously its interests.
	Settlement of NewMarket Corporation civil complaint
	As we have previously disclosed, the Company and its subsidiaries, Alcor Chemie Vertriebs GmbH and Innospec Limited, were the subject of two civil actions brought by NewMarket Corporation and its subsidiary, Afton Chemical Corporation (collectively, “NewMarket”). NewMarket and the Company agreed to settle these actions pursuant to the terms of a settlement agreement between them signed on September 13, 2011 which provided for mutual releases of the parties and dismissal of the actions with prejudice. Under the settlement agreement, the Company will pay NewMarket an aggregate amount of approximately $45.0 million, payable in a combination of cash, a promissory note and stock, of which $25.0 million was paid in cash in September 2011, $15.0 million is payable in three equal annual installments under the promissory note (carrying simple interest at 1% per annum) and approximately $5.0 million was paid in the form of 195,313 shares of the Company’s common stock transferred to NewMarket in September 2011. The first installment of the promissory note was paid on September 7, 2012 and the second installment was paid on September 9, 2013.
	Other legal matters
	While we are involved from time to time in claims and legal proceedings that result from, and are incidental to, the conduct of our business including business and commercial litigation, employee and product liability claims, there are no other material pending legal proceedings to which the Company or any of its subsidiaries is a party, or of which any of their property is subject. It is possible however, that an adverse resolution of an unexpectedly large number of such individual items could in the aggregate have a material adverse effect on results of operations for a particular year or quarter.
	Guarantees
	The Company and certain of the Company’s consolidated subsidiaries are contingently liable for certain obligations of affiliated companies primarily in the form of guarantees of debt and performance under contracts entered into as a normal business practice. This includes guarantees of non-U.S. excise taxes and customs duties. As at December 31, 2013, such contingent liabilities which are not recognized as liabilities in the consolidated financial statements amounted to $3.8 million.
	Under the terms of the guarantee arrangements, generally the Company would be required to perform should the affiliated company fail to fulfill its obligations under the arrangements. In some cases, the guarantee arrangements have recourse provisions that would enable the Company to recover any payments made under the terms of the guarantees from securities held of the guaranteed parties’ assets.
	The Company and its affiliates have numerous long-term sales and purchase commitments in their various business activities, which are expected to be fulfilled with no adverse consequences material to the Company.

Stockholders_Equity

Stockholders' Equity	12 Months Ended
	Dec. 31, 2013
Equity [Abstract]	'
Stockholders' Equity	'
	Note 18.    Stockholders’ Equity
		Common Stock						Treasury Stock
	(number of shares in thousands)	2013		2012		2011		2013			2012			2011
	At January 1		29,555		29,555		29,555		6,222			6,507			5,851
	Exercise of options		0		0		0		(632	)		(333	)		(236	)
	Acquisition-related stock issued		0		0		0		(471	)		0			0
	Stock purchases		0		0		0		89			48			1,087
	Settlement of NewMarket		0		0		0		0			0			(195	)
	Corporation civil complaint
	At December 31		29,555		29,555		29,555		5,208			6,222			6,507
	At December 31, 2013, the Company had authorized common stock of 40,000,000 shares (2012 – 40,000,000). Issued shares at December 31, 2013, were 29,554,500 (2012 – 29,554,500) and treasury stock amounted to 5,207,947 shares (2012 – 6,222,076).

StockBased_Compensation_Plans

Stock-Based Compensation Plans	12 Months Ended
	Dec. 31, 2013
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]	'
Stock-Based Compensation Plans	'
	Note 19.    Stock-Based Compensation Plans
	Stock option plans
	The Company has five active stock option plans, two of which provide for the grant of stock options to employees, one provides for the grant of stock options to non-employee directors, and another provides for the grant of stock options to key executives on a matching basis provided they use a proportion of their annual bonus to purchase common stock in the Company on the open market or from the Company. The fifth plan is a savings plan which provides for the grant of stock options to all Company employees provided they commit to make regular savings over a pre-defined period which can then be used to purchase common stock upon vesting of the options. The stock options have vesting periods ranging from 24 months to 6 years and in all cases stock options granted expire within 10 years of the date of grant. All grants are at the sole discretion of the Compensation Committee of the Board of Directors. Grants may be priced at market value or at a premium or discount. The aggregate number of shares of common stock reserved for issuance which can be granted under the plans is 2,640,000.
	The fair value of stock options is measured on the grant date using either the Black-Scholes model, or in cases where performance criteria are dependent upon external factors such as the Company’s stock price, using a Monte Carlo model. The following weighted average assumptions were used to determine the grant-date fair value of options:
		2013			2012			2011
	Dividend yield		0.11	%		0	%		0.2	%
	Expected life		5 years			5 years			5 years
	Volatility		41.1	%		60.1	%		78.3	%
	Risk free interest rate		0.46	%		0.43	%		1.22	%
	The following table summarizes the transactions of the Company’s stock option plans for the year ended December 31, 2013:
		Number of			Weighted			Weighted
		Options			Average			Average
					Exercise Price			Grant-Date
								Fair Value
	Outstanding at December 31, 2012		1,001,241		$	6.27
	Granted – at discount		78,828		$	0		$	36.3
	– at market value		22,161		$	41.27		$	16.09
	Exercised		(629,152	)	$	5.96
	Forfeited		(25,688	)	$	6.21
	Outstanding at December 31, 2013		447,390		$	7.33
	At December 31, 2013, there were 186,741 stock options that were exercisable, 77,001 had performance conditions attached.
	The Company’s policy is to issue shares from treasury stock to holders of stock options who exercise those options, but if sufficient treasury stock is not available, the Company will issue previously unissued shares of stock to holders of stock options who exercise options.
	The total compensation cost for 2013, 2012 and 2011 was $2.5 million, $3.1 million and $3.1 million, respectively. The total intrinsic value of options exercised in 2013, 2012 and 2011 was $4.7 million, $1.5 million and $2.2 million, respectively.
	The total compensation cost related to non-vested stock options not yet recognized at December 31, 2013 was $2.7 million and this cost is expected to be recognized over the weighted-average period of 2.07 years.
	The cash tax benefit realized from stock option exercises totaled $5.7 million, $2.7 million and $1.7 million in 2013, 2012 and 2011, respectively. The excess tax benefit classified in financing activities was $3.8 million, $2.2 million and $1.1 million in 2013, 2012 and 2011, respectively.
	No stock options awards were modified in 2013, 2012 or 2011.
	Stock equivalent units
	The Company awards Stock Equivalent Units (“SEUs”) from time to time as a long-term performance incentive. SEUs are cash settled equity instruments conditional on certain performance criteria and linked to the Innospec Inc. share price. SEUs have vesting periods ranging from 11 months to 4 years and in all cases SEUs granted expire within 10 years of the date of grant. Grants may be priced at market value or at a premium or discount. There is no limit to the number of SEUs that can be granted. As at December 31, 2013 the liability for SEUs of $12.1 million is located in accrued liabilities in the consolidated balance sheets until they are cash settled.
	The fair value of SEUs is measured at the balance sheet date using either the Black-Scholes model, or in cases where performance criteria are dependent upon external factors such as the Company’s stock price, using a Monte Carlo model. The following assumptions were used to determine the fair value of SEUs at the balance sheet dates:
		2013			2012			2011
	Dividend yield		1.08	%		0	%		0	%
	Volatility		37.61	%		43.8	%		64.2	%
	Risk free interest rate		0.78	%		0.36	%		0.36	%
	The following table summarizes the transactions of the Company’s SEUs for the year ended December 31, 2013:
		Number			Weighted			Weighted
		of SEUs			Average			Average
					Exercise Price			Grant-Date
								Fair Value
	Outstanding at December 31, 2012		623,828		$	2.95
	Granted – at discount		59,028		$	0		$	35.29
	– at market value		6,970		$	41.31		$	16.09
	Exercised		(281,703	)	$	2.25
	Forfeited		(4,861	)	$	5.04
	Outstanding at December 31, 2013		403,262		$	3.64
	At December 31, 2013, there were 64,019 SEUs that were exercisable, 57,677 had performance conditions attached.
	The charges for SEUs are spread over the life of the award subject to a revaluation to fair value each quarter. The revaluation may result in a charge or a credit to the income statement in the quarter dependent upon our share price and other performance criteria.
	The total compensation cost for 2013, 2012 and 2011 was $7.1 million, $6.8 million and $5.9 million, respectively. The total intrinsic value of SEUs exercised in 2013, 2012 and 2011 was $2.2 million, $1.3 million and $0.4 million, respectively.
	The weighted-average remaining vesting period of non-vested SEUs is 0.80 years.
	Long-term incentive plan
	An additional long-term incentive plan was in place to reward selected executives for delivering exceptional performance. Under this plan a discretionary bonus was payable to eligible executives if the Innospec share performance out-performed that of competitors, as measured by the Russell 2000 Index, by a minimum of 10% over the five years from January 2008 to December 2012. The maximum bonus under this plan was $8 million and was ultimately earned by the participants. The fair value of these liability cash-settled stock appreciation rights was calculated on a quarterly basis using a Monte Carlo model and is summarized as follows:
	(in millions)	2013			2012			2011
	Balance at January 1	$	1.3		$	2.2		$	0.8
	Compensation charge		0			5.8			1.4
	Cash paid		(1.3	)		(6.7	)		0
	Balance at December 31	$	0		$	1.3		$	2.2
	The following assumptions were used in the Monte Carlo model:
		2012			2011
	Dividend yield		0	%		0	%
	Volatility		0	%		53.5	%
	Risk free interest rate		0.36	%		0.36	%

Reclassifications_Out_of_Accum

Reclassifications Out of Accumulated Other Comprehensive Income/(Loss)	12 Months Ended
	Dec. 31, 2013
Text Block [Abstract]	'
Reclassifications Out of Accumulated Other Comprehensive Income/(Loss)	'
	Note 20.    Reclassifications out of Accumulated Other Comprehensive Income/(Loss)
	Reclassifications out of accumulated other comprehensive loss for 2013 were:
	(in millions)		Amount			Affected Line Item in the
			Reclassified			Statement where
	Details about AOCL Components		from AOCL			Net Income is Presented
	Derivative instruments:
	Realized gain/(loss) on derivative instruments		$	(0.1	)	Cost of goods sold
				(0.1	)	Total before tax
				0		Income tax expense
			$	(0.1	)	Net of tax
	Defined benefit pension plan items:
	Amortization of prior service credit		$	(1.3	)	See (¹) below
	Amortization of actuarial net losses			6.2		See (¹) below
				4.9		Total before tax
				(1.1	)	Income tax expense
				3.8		Net of tax
	Total reclassifications		$	3.7		Net of tax
	-1	These items are included in the computation of net periodic pension cost. See Note 9 for additional information.
	Changes in accumulated other comprehensive loss for 2013, net of tax, were:
	(in millions)		Unrealized			Defined			Cumulative			Total
			Gains/			Benefit			Translation
			(Losses) on			Pension			Adjustments
			Derivative			Plan Items
			Instruments
	Balance at December 31, 2012		$	0.1		$	(117.3	)	$	(34.9	)	$	(152.1	)
	Other comprehensive income/(loss) before reclassifications			0			0			1.2			1.2
	Actuarial net losses arising during the year						(6.7	)					(6.7	)
	Amounts reclassified from AOCL			(0.1	)		3.8			0			3.7
	Net current period other comprehensive income/(loss)			(0.1	)		(2.9	)		1.2			(1.8	)
	Balance at December 31, 2013		$	0		$	(120.2	)	$	(33.7	)	$	(153.9	)

Recently_Issued_Accounting_Pro

Recently Issued Accounting Pronouncements	12 Months Ended
	Dec. 31, 2013
Accounting Changes And Error Corrections [Abstract]	'
Recently Issued Accounting Pronouncements	'
	Note 21.    Recently Issued Accounting Pronouncements
	In July 2013, the FASB issued ASU 2013-11, Presentation of an Unrecognized Tax Benefit when a Net Operating Loss Carryforward, a Similar Tax Loss, or a Tax Credit Carryforward Exists (“ASU 2013-11”), which requires an unrecognized tax benefit to be presented in the financial statements as a reduction to a deferred tax asset for a net operating loss carryforward, similar tax loss, or a tax credit carryforward. To the extent the tax benefit is not available at the reporting date under the governing tax law or if the entity does not intend to use the deferred tax asset for such purpose, the unrecognized tax benefit should be presented as a liability and not combined with deferred tax assets. ASU 2013-11 is effective for annual periods, and interim periods within those years, beginning after December 15, 2013. The amendments are to be applied to all unrecognized tax benefits that exist as of the effective date and may be applied retrospectively to each prior reporting period presented. We do not expect a material impact from the adoption of this guidance on our consolidated financial statements.
	In February 2013, the FASB issued ASU 2013-02, Other Comprehensive Income (Topic 220): Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income. The amendments in ASU 2013-02 require the Company to report the effect of significant reclassifications out of accumulated other comprehensive income on the respective line items in net income, either on the face of the income statement or in the notes, if the amount being reclassified is required under GAAP to be reclassified in its entirety to net income in the same reporting period. For other amounts not required by GAAP to be reclassified in their entirety to net income in the same reporting period, an entity is required to cross-reference other disclosures which provide additional information about the amounts. The guidance is effective prospectively for reporting periods beginning after December 15, 2012. As this guidance provides only presentation requirements, the adoption of this standard did not impact the Company’s results of operations, financial position or cash flows.
	In July 2012, the FASB issued ASU 2012-02, Intangibles – Goodwill and Other (Topic 350): Testing Indefinite-Lived Intangible Assets for Impairment. ASU 2012-02 simplifies how entities test indefinite-lived intangible assets, other than goodwill, for impairment and permits an entity to first assess qualitative factors to determine whether it is more likely than not that the indefinite-lived intangible asset is impaired. The amendments are effective for annual and interim indefinite-lived intangible asset impairment tests performed for fiscal years beginning after September 15, 2012 (early adoption is permitted). The implementation of the amended accounting guidance has not had a material impact on our consolidated financial statements.
	In December 2011, the FASB issued ASU 2011-11, Balance Sheet (Topic 210): Disclosures about Offsetting Assets and Liabilities. The objective of ASU 2011-11 is to facilitate convergence of U.S. GAAP and International Financial Reporting Standards and improve the comparability of statements of financial position. Entities are required to disclose both gross information and net information about both instruments and transactions eligible for offset in the statement of financial position and instruments and transactions subject to an agreement similar to a master netting arrangement. This scope would include derivatives, sale and repurchase agreements, and securities borrowing and securities lending arrangements. This guidance is effective for annual reporting periods beginning on or after January 1, 2013, and interim periods within those annual periods. Entities should provide the disclosures required by these amendments retrospectively for all comparative periods presented. The implementation of the amended accounting guidance has not had a material impact on our consolidated financial statements.

Related_Party_Transactions

Related Party Transactions	12 Months Ended
	Dec. 31, 2013
Related Party Transactions [Abstract]	'
Related Party Transactions	'
	Note 22.    Related Party Transactions
	Mr. Robert I. Paller has been a non-executive director of the Company since November 1, 2009. The Company has retained and continues to retain Smith, Gambrell & Russell, LLP (“SGR”), a law firm with which Mr. Paller holds a position. In 2013, 2012 and 2011 the Company incurred fees payable to SGR of $1.0 million, $0.8 million and $6.5 million, respectively. As at December 31, 2013, the amount due to SGR from the Company was $0.2 million.

Subsequent_Events

Subsequent Events	12 Months Ended
	Dec. 31, 2013
Subsequent Events [Abstract]	'
Subsequent Events	'
	Note 23.    Subsequent Events
	The Company has evaluated subsequent events through the date that the consolidated financial statements were issued, and has concluded that no additional disclosures are required in relation to events subsequent to the balance sheet date.

Accounting_Policies_Policies

Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2013
Accounting Changes And Error Corrections [Abstract]	'
Revision of Prior Years	'
	Revision of Prior Years
	In connection with the preparation of the consolidated financial statements for the fourth quarter of 2013, the Company identified an error in the treatment of the amortization of actuarial net losses. The Company determined that the Market Related Value of Assets (“MRVA”) for Innospec Limited’s United Kingdom Pension Plan has been overstated each year since 2003. The market-related value of plan assets is either fair value if the employer does not defer gains or losses on plan assets, or a calculated value that recognizes changes in fair value in a systematic and rational manner over not more than five years, when the expected long-term rate of return is used to determine net periodic postretirement benefit cost. The overstated MRVA is used to determine the size of “the corridor” under GAAP which has resulted in an understatement of amortization of actuarial net losses within the pension expense each year since 2004. This error affects the non-cash pension expenses in the financial statements for the years ended 2012 and 2011 as reported in this 2013 Form 10-K. For quarterly reporting purposes the whole annual non-cash pension expense adjustment has been reflected in the fourth quarter for each year as the impact on the individual quarters is not considered to be material.
	The Company has applied SEC Staff Accounting Bulletin (SAB) No. 108, Considering the Effects of Prior Year Misstatements when Quantifying Misstatements in Current Year Financial Statements. SAB No. 108 states that registrants must quantify the impact of correcting all misstatements, including both the carryover (iron curtain method) and reversing (rollover method) effects of prior-year misstatements on the current-year financial statements, and by evaluating the error measured under each method in light of quantitative and qualitative factors.
	Under SAB No. 108, prior-year misstatements which, if corrected in the current year would be material to the current year, must be corrected by adjusting prior year financial statements, even though such correction previously was and continues to be immaterial to the prior-year financial statements. Correcting prior-year financial statements for such “immaterial errors” does not require previously filed reports to be amended.
	In accordance with accounting guidance presented in ASC 250-10 (SEC Staff Accounting Bulletin No. 99, Materiality), the Company assessed the materiality of the error and concluded that it was not material to any of the Company’s previously issued financial statements taken as a whole.
	Innospec has calculated the understatement of the non-cash pension expense, net of tax, to be $16.1 million as at 1 January 2011, $1.8 million in 2011 and $1.4 million in 2012. Adjustments have been made as follows:
		Year Ended December 31, 2012
	(in millions)	As			Adjustment			As Revised
		Previously
		Reported
	Selling, general and administrative expenses	$	(117.1	)	$	(1.9	)	$	(119.0	)
	Operating income		98.4			(1.9	)		96.5
	Income before income taxes		95.2			(1.9	)		93.3
	Income taxes		(26.9	)		0.5			(26.4	)
	Net income		68.3			(1.4	)		66.9
	Retained earnings		281			(19.3	)		261.7
	Accumulated other comprehensive loss		(171.4	)		19.3			(152.1	)
		Year Ended December 31, 2011
	(in millions)	As			Adjustment			As Revised
		Previously
		Reported
	Selling, general and administrative expenses	$	(155.9	)	$	(2.4	)	$	(158.3	)
	Operating income		49.6			(2.4	)		47.2
	Income before income taxes		52.6			(2.4	)		50.2
	Income taxes		(3.7	)		0.6			(3.1	)
	Net income		48.9			(1.8	)		47.1
	Retained earnings		259.4			(17.9	)		241.5
	Accumulated other comprehensive loss		(120.0	)		17.9			(102.1	)
		As at January 1, 2011
	(in millions)	As			Adjustment			As Revised
		Previously
		Reported
	Retained earnings	$	210.5		$	(16.1	)	$	194.4
	Accumulated other comprehensive loss		(131.6	)		16.1			(115.5	)
Basis of preparation	'
	Basis of preparation: The consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States of America and include all subsidiaries of the Company where the Company has a controlling financial interest. All significant intercompany accounts and balances have been eliminated upon consolidation. All acquisitions are accounted for as purchases and the results of operations of the acquired businesses are included in the consolidated financial statements from the date of acquisition.
Use of estimates	'
	Use of estimates: The preparation of the consolidated financial statements, in accordance with generally accepted accounting principles in the United States of America, requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. Actual results could differ from those estimates.
Cash equivalents	'
	Cash equivalents: Investment securities with maturities of three months or less when purchased are considered to be cash equivalents.
Short-term investments	'
	Short-term investments: Investment securities with maturities of more than 3 months and less than 12 months when purchased are considered to be short-term investments.
Trade and other accounts receivable	'
	Trade and other accounts receivable: The Company records trade and other accounts receivable at net realizable value and maintains allowances for customers not making required payments. The Company determines the adequacy of allowances by periodically evaluating each customer receivable considering our customer’s financial condition, credit history and current economic conditions.
Inventories	'
	Inventories: Inventories are stated at the lower of cost (FIFO method) or market value. Cost includes materials, labor and an appropriate proportion of plant overheads. The Company accrues volume discounts where it is probable that the required volume will be attained and the amount can be reasonably estimated. The discounts are recorded as a reduction in the cost of materials based on projected purchases over the period of the agreement. Inventories are adjusted for estimated obsolescence and written down to market value based on estimates of future demand and market conditions.
Property, plant and equipment	'
	Property, plant and equipment: Property, plant and equipment are stated at cost less accumulated depreciation. Depreciation is provided over the estimated useful lives of the assets using the straight-line method and is allocated between cost of goods sold and operating expenses. The cost of additions and improvements are capitalized. Maintenance and repairs are charged to expenses. When assets are sold or retired the associated cost and accumulated depreciation are removed from the consolidated financial statements and any related gain or loss is included in earnings. The estimated useful lives of the major classes of depreciable assets are as follows:
	Buildings		7 to 25 years
	Equipment		3 to 10 years
Goodwill and other intangible assets	'
	Goodwill and other intangible assets: Goodwill and other intangible assets deemed to have indefinite lives are not amortized but are subject to at least annual impairment tests based on projected post-tax cash flows discounted at the Company’s weighted average cost of capital. The annual measurement date for impairment testing of the goodwill relating to the Fuel Specialties and Performance Chemicals segments is December 31. At this date we performed annual impairment tests and concluded that there had been no impairment of goodwill in respect of those reporting segments. The Company capitalizes software development costs, including licenses, subsequent to the establishment of technological feasibility. Other intangible assets deemed to have finite lives, including software development costs and licenses, are amortized using the straight-line method over their estimated useful lives and tested for any potential impairment when events occur or circumstances change which suggest that an impairment may have occurred.
Deferred finance costs	'
	Deferred finance costs: The costs relating to debt financing are capitalized, separately disclosed in the consolidated balance sheets and amortized using the effective interest method over the expected life of the debt financing facility.
Impairment of long-lived assets	'
	Impairment of long-lived assets: The Company reviews the carrying value of its long-lived assets, including buildings and equipment, whenever changes in circumstances suggest that the carrying values may be impaired. In order to facilitate this test the Company groups together assets at the lowest possible level for which cash flow information is available. Undiscounted future cash flows expected to result from the assets are compared with the carrying value of the assets and if they are lower an impairment loss may be recognized. The amount of the impairment loss is the difference between the fair value and the carrying value of the assets. Fair values are determined using post-tax cash flows discounted at the Company’s weighted average cost of capital.
Derivative instruments	'
	Derivative instruments: The Company uses various derivative instruments including forward currency contracts, options, interest rate swaps and commodity swaps to manage certain exposures. These instruments are entered into under the Company’s corporate risk management policy to minimize exposure and are not for speculative trading purposes. The Company recognizes all derivatives as either non-current assets or liabilities in the consolidated balance sheet and measures those instruments at fair value. Changes in the fair value of derivatives that are not designated as hedges, or do not meet the requirements for hedge accounting, are recognized in earnings. Derivatives which are designated as hedges are tested for effectiveness on a quarterly basis, and marked to market. The ineffective portion of the derivative’s change in value is recognized in earnings. The effective portion is recognized in other comprehensive income until the hedged item is recognized in earnings.
Environmental compliance and remediation	'
	Environmental compliance and remediation: Environmental compliance costs include ongoing maintenance, monitoring and similar costs. We recognize environmental liabilities when they are probable and costs can be reasonably estimated, and asset retirement obligations when there is a legal obligation and costs can be reasonably estimated. Such accruals are adjusted as further information develops or circumstances change. Costs of future obligations are discounted to their present values using the Company’s credit-adjusted risk-free rate.
Acquisition-related contingent and deferred consideration	'
	Acquisition-related contingent and deferred consideration: Deferred consideration payable in cash is discounted to its fair value. Where deferred consideration is contingent upon pre-determined financial targets, an estimate of the fair value of the likely consideration payable is made. This contingent deferred consideration is re-assessed annually and a corresponding adjustment is recognized in operating income, and the associated liability, to reflect the passage of time accretion expense and any revisions to the amount or timing of the initial measurement.
Revenue recognition	'
	Revenue recognition: The Company supplies products to customers from its various manufacturing sites, and in some instances from containers held on customer sites, under a variety of standard shipping terms and conditions. In each case revenue is recognized when legal title, which is defined and generally accepted in the standard terms and conditions, and risk of loss transfers between the Company and the customer. Provisions for sales discounts and rebates to customers are based upon the terms of sales contracts and are recorded in the same period as the related sales as a deduction from revenue. The Company estimates the provision for sales discounts and rebates based on the terms of each agreement at the time of shipping.
Components of net sales	'
	Components of net sales: All amounts billed to customers relating to shipping and handling are classified as net sales. Shipping and handling costs incurred by the Company are classified as cost of goods sold.
Components of cost of goods sold	'
	Components of cost of goods sold: Cost of goods sold is comprised of raw material costs including inbound freight, duty and non-recoverable taxes, inbound handling costs associated with the receipt of raw materials, packaging materials, manufacturing costs including labor costs, maintenance and utility costs, plant and engineering overheads, amortization expense for certain other intangible assets, warehousing and outbound shipping costs and handling costs. Inventory losses and provisions and the costs of customer claims are also recognized in the cost of goods line item.
Components of selling, general and administrative expenses	'
	Components of selling, general and administrative expenses: Selling expenses comprise the costs of the direct sales force, and the sales management and customer service departments required to support them. It also comprises commission charges, the costs of sales conferences and trade shows, the cost of advertising and promotions, amortization expense for certain other intangible assets, and the cost of bad and doubtful debts. General and administrative expenses comprise the cost of support functions including accounting, human resources, information technology and the cost of group functions including corporate management, finance, tax, treasury, investor relations and legal departments. Provision of management’s best estimate of legal and settlement costs for litigation in which the Company is involved is made and reported in the administrative expense line item.
Research and development expenses	'
	Research and development expenses: Research, development and testing costs are expensed to the income statement as incurred.
Earnings per share	'
	Earnings per share: Basic earnings per share is based on the weighted average number of common shares outstanding during the period. Diluted earnings per share includes the effect of options that are dilutive and outstanding during the period.
Foreign currencies	'
	Foreign currencies: The Company’s policy is that foreign exchange differences arising on the translation of the balance sheets of entities that have functional currencies other than the U.S. dollar are taken to a separate equity reserve, the cumulative translation adjustment. In entities where the U.S. dollar is the functional currency no gains or losses on translation occur, and gains or losses on monetary assets relating to currencies other than the U.S. dollar are taken to the income statement in other net income/(expense). Other foreign exchange gains or losses are also included in other net income/(expense) in the income statement.
Share based compensation plans	'
	Share based compensation plans: The Company accounts for employee stock options and stock equivalent units under the fair value method. Stock options are fair valued at the grant date and the fair value is recognized straight-line over the vesting period of the option. Stock equivalent units are fair valued at each balance sheet date and the fair value is spread over the remaining vesting period of the unit.
Pension plans and other post-employment benefits	'
	Pension plans and other post-employment benefits: The Company recognizes the funded status of defined benefit post-retirement plans on the consolidated balance sheets and changes in the funded status in comprehensive income. The measurement date of the plan’s funded status is the same as the Company’s fiscal year-end. Prior service costs and credits and actuarial gains and losses are amortized over the average remaining life expectancy of the inactive participants using the corridor method.
Income taxes	'
	Income taxes: The Company provides for income taxes by recognizing deferred tax assets and liabilities for the expected future tax consequences of temporary differences between the financial statement carrying amounts and the relevant tax bases of the assets and liabilities. When appropriate, the Company evaluates the need for a valuation allowance to reduce deferred tax assets. The Company recognizes future tax benefits to the extent that realization of such benefits is more likely than not. The effect on deferred taxes of a change in tax rates is recognized in the period that includes the enactment date. Income tax positions must meet a more likely than not recognition criteria to be recognized. The Company recognizes accrued interest and penalties associated with uncertain tax positions as part of income taxes in our consolidated statements of income.
Presentation of an Unrecognized Tax Benefit	'
	In July 2013, the FASB issued ASU 2013-11, Presentation of an Unrecognized Tax Benefit when a Net Operating Loss Carryforward, a Similar Tax Loss, or a Tax Credit Carryforward Exists (“ASU 2013-11”), which requires an unrecognized tax benefit to be presented in the financial statements as a reduction to a deferred tax asset for a net operating loss carryforward, similar tax loss, or a tax credit carryforward. To the extent the tax benefit is not available at the reporting date under the governing tax law or if the entity does not intend to use the deferred tax asset for such purpose, the unrecognized tax benefit should be presented as a liability and not combined with deferred tax assets. ASU 2013-11 is effective for annual periods, and interim periods within those years, beginning after December 15, 2013. The amendments are to be applied to all unrecognized tax benefits that exist as of the effective date and may be applied retrospectively to each prior reporting period presented. We do not expect a material impact from the adoption of this guidance on our consolidated financial statements.
Other Comprehensive Income	'
	In February 2013, the FASB issued ASU 2013-02, Other Comprehensive Income (Topic 220): Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income. The amendments in ASU 2013-02 require the Company to report the effect of significant reclassifications out of accumulated other comprehensive income on the respective line items in net income, either on the face of the income statement or in the notes, if the amount being reclassified is required under GAAP to be reclassified in its entirety to net income in the same reporting period. For other amounts not required by GAAP to be reclassified in their entirety to net income in the same reporting period, an entity is required to cross-reference other disclosures which provide additional information about the amounts. The guidance is effective prospectively for reporting periods beginning after December 15, 2012. As this guidance provides only presentation requirements, the adoption of this standard did not impact the Company’s results of operations, financial position or cash flows.
Intangibles - Goodwill and Other	'
	In July 2012, the FASB issued ASU 2012-02, Intangibles – Goodwill and Other (Topic 350): Testing Indefinite-Lived Intangible Assets for Impairment. ASU 2012-02 simplifies how entities test indefinite-lived intangible assets, other than goodwill, for impairment and permits an entity to first assess qualitative factors to determine whether it is more likely than not that the indefinite-lived intangible asset is impaired. The amendments are effective for annual and interim indefinite-lived intangible asset impairment tests performed for fiscal years beginning after September 15, 2012 (early adoption is permitted). The implementation of the amended accounting guidance has not had a material impact on our consolidated financial statements.
Balance Sheet	'
	In December 2011, the FASB issued ASU 2011-11, Balance Sheet (Topic 210): Disclosures about Offsetting Assets and Liabilities. The objective of ASU 2011-11 is to facilitate convergence of U.S. GAAP and International Financial Reporting Standards and improve the comparability of statements of financial position. Entities are required to disclose both gross information and net information about both instruments and transactions eligible for offset in the statement of financial position and instruments and transactions subject to an agreement similar to a master netting arrangement. This scope would include derivatives, sale and repurchase agreements, and securities borrowing and securities lending arrangements. This guidance is effective for annual reporting periods beginning on or after January 1, 2013, and interim periods within those annual periods. Entities should provide the disclosures required by these amendments retrospectively for all comparative periods presented. The implementation of the amended accounting guidance has not had a material impact on our consolidated financial statements.

Accounting_Policies_Tables

Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2013
Accounting Policies [Abstract]	'
Revision of Prior Year Adjustments	'
	Adjustments have been made as follows:
		Year Ended December 31, 2012
	(in millions)	As			Adjustment			As Revised
		Previously
		Reported
	Selling, general and administrative expenses	$	(117.1	)	$	(1.9	)	$	(119.0	)
	Operating income		98.4			(1.9	)		96.5
	Income before income taxes		95.2			(1.9	)		93.3
	Income taxes		(26.9	)		0.5			(26.4	)
	Net income		68.3			(1.4	)		66.9
	Retained earnings		281			(19.3	)		261.7
	Accumulated other comprehensive loss		(171.4	)		19.3			(152.1	)
		Year Ended December 31, 2011
	(in millions)	As			Adjustment			As Revised
		Previously
		Reported
	Selling, general and administrative expenses	$	(155.9	)	$	(2.4	)	$	(158.3	)
	Operating income		49.6			(2.4	)		47.2
	Income before income taxes		52.6			(2.4	)		50.2
	Income taxes		(3.7	)		0.6			(3.1	)
	Net income		48.9			(1.8	)		47.1
	Retained earnings		259.4			(17.9	)		241.5
	Accumulated other comprehensive loss		(120.0	)		17.9			(102.1	)
		As at January 1, 2011
	(in millions)	As			Adjustment			As Revised
		Previously
		Reported
	Retained earnings	$	210.5		$	(16.1	)	$	194.4
	Accumulated other comprehensive loss		(131.6	)		16.1			(115.5	)
Estimated Useful Lives of Major Classes of Depreciable Assets	'
	The estimated useful lives of the major classes of depreciable assets are as follows:
	Buildings		7 to 25 years
	Equipment		3 to 10 years

Segmental_Reporting_and_Geogra1

Segmental Reporting and Geographical Area Data (Tables)	12 Months Ended
	Dec. 31, 2013
Segment Reporting [Abstract]	'
Segmental Reporting	'
	The following table analyzes sales and other financial information by the Company’s reportable segments:
	(in millions)	2013			2012			2011
	Net sales:
	Fuel Specialties	$	567.4		$	527.2		$	521.2
	Performance Chemicals		192.4			179.6			177
	Octane Additives		59			69.6			76.2
		$	818.8		$	776.4		$	774.4
	Gross profit:
	Fuel Specialties	$	181.1		$	158.7		$	149.3
	Performance Chemicals		46.3			43.8			40.6
	Octane Additives		27.8			33.9			36.5
		$	255.2		$	236.4		$	226.4
	Operating income:
	Fuel Specialties	$	92.7		$	87.6		$	81.7
	Performance Chemicals		23.6			24.3			22.6
	Octane Additives		21.5			26			(22.4	)
	Pension credit/(charge)		(2.3	)		(1.6	)		(2.9	)
	Corporate costs		(43.4	)		(38.5	)		(29.2	)
	Restructuring charge		(0.2	)		(0.2	)		(0.6	)
	Impairment of Octane Additives segment goodwill		(1.3	)		(1.2	)		(2.0	)
	Profit on disposal, net		0			0.1			0
	Total operating income	$	90.6		$	96.5		$	47.2
	Identifiable assets at year end:
	Fuel Specialties	$	446.4		$	356.6		$	281.5
	Performance Chemicals		176.8			113.4			106.7
	Octane Additives		42			48.9			51.5
	Corporate		128.8			60.5			129.1
		$	794		$	579.4		$	568.8
Segment Reporting on Basis of Geographical Location	'
	Goodwill has not been allocated by geographical location on the grounds that it would be impracticable to do so.
	(in millions)	2013			2012			2011
	Net sales by source:
	United States	$	276.1		$	274.1		$	265.6
	United Kingdom		502.4			475.1			482.8
	Rest of Europe		129.1			142.8			151.7
	Other		0.2			0.5			0.9
	Sales between areas		(89.0	)		(116.1	)		(126.6	)
		$	818.8		$	776.4		$	774.4
	Net sales by destination:
	United States	$	278.7		$	272.4		$	248.2
	United Kingdom		30			38.8			48.5
	Rest of Europe		325.5			331			304.2
	Other		184.6			134.2			173.5
		$	818.8		$	776.4		$	774.4
	Income before income taxes:
	United States	$	10		$	5.6		$	(42.6	)
	United Kingdom		43.7			36.3			36.6
	Rest of Europe		40.4			52.6			58.2
	Impairment of Octane Additives segment goodwill		(1.3	)		(1.2	)		(2.0	)
		$	92.8		$	93.3		$	50.2
	Long-lived assets at year end:
	United States	$	148.2		$	31.5		$	22
	United Kingdom		29.4			28.7			32.4
	Rest of Europe		11.5			11.5			10.9
		$	189.1		$	71.7		$	65.3
	Identifiable assets at year end:
	United States	$	291		$	174.1		$	123.2
	United Kingdom		261.5			192.1			253.8
	Rest of Europe		53.2			63.8			49.8
	Other		0.4			0.4			0.5
	Goodwill		187.9			149			141.5
		$	794		$	579.4		$	568.8

Earnings_Per_Share_Tables

Earnings Per Share (Tables)	12 Months Ended
	Dec. 31, 2013
Earnings Per Share [Abstract]	'
Summary of Earnings Per Share	'
	Per share amounts are computed as follows:
		2013		2012		2011
	Numerator (in millions):
	Net income available to common stockholders	$	77.8	$	66.9	$	47.1
	Denominator (in thousands):
	Weighted average common shares outstanding		23,651		23,187		23,568
	Dilutive effect of stock options and awards		505		663		952
	Denominator for diluted earnings per share		24,156		23,850		24,520
	Net income per share, basic:	$	3.29	$	2.89	$	2
	Net income per share, diluted:	$	3.22	$	2.81	$	1.92

Property_Plant_and_Equipment_T

Property, Plant and Equipment (Tables)	12 Months Ended
	Dec. 31, 2013
Property Plant And Equipment [Abstract]	'
Schedule of Property, Plant and Equipment	'
	Property, plant and equipment consists of the following:
	(in millions)	2013			2012
	Land	$	7.5		$	7.2
	Buildings		10.8			6.5
	Equipment		152.9			129
	Work in progress		3.9			3.5
			175.1			146.2
	Less accumulated depreciation		(114.7	)		(96.4	)
		$	60.4		$	49.8

Goodwill_Tables

Goodwill (Tables)	12 Months Ended
	Dec. 31, 2013
Summary of Goodwill	'
	The following table analyzes goodwill for 2013 and 2012.
	(in millions)		Fuel			Performance		Octane			Total
			Specialties			Chemicals		Additives
	At January 1, 2012
	Gross cost (1)		$	108.8		$	30.1	$	236.6		$	375.5
	Accumulated impairment losses			0			0		(234.0	)		(234.0	)
	Net book amount			108.8			30.1		2.6			141.5
	Exchange effect			0.1			0		(0.1	)		0
	Acquisitions			8.7			0		0			8.7
	Impairment losses			0			0		(1.2	)		(1.2	)
	At December 31, 2012
	Gross cost (1)			117.6			30.1		236.5			384.2
	Accumulated impairment losses			0			0		(235.2	)		(235.2	)
	Net book amount			117.6			30.1		1.3			149
	Exchange effect			0			0		0			0
	Acquisitions			22.9			16.7		0			39.6
	Adjustments to purchase price allocation			0.6			0		0			0.6
	Impairment losses			0			0		(1.3	)		(1.3	)
	At December 31, 2013
	Gross cost (1)			141.1			46.8		236.5			424.4
	Accumulated impairment losses			0			0		(236.5	)		(236.5	)
	Net book amount		$	141.1		$	46.8	$	0		$	187.9
	-1	Gross cost is net of $8.7 million, $0.3 million and $289.5 million of historical accumulated amortization in respect of the Fuel Specialties, Performance Chemicals and Octane Additives reporting segments, respectively.
Schedule of Pro Forma Financial Information	'
	For illustrative purposes only pro forma information of the enlarged group is provided below but is not necessarily indicative of what the financial position or results of operations would have been had the acquisitions of Strata, Chemsil, Chemtec and Bachman been completed as of January 1, 2012. In addition, the unaudited pro forma financial information is not indicative of, nor does it purport to project, the future financial position of operating results of the enlarged group.
	(in millions, except per share data)		2013			2012
	Net sales		$	913.1		$	904.6
	Net income		$	85.1		$	77.2
	Earnings per share – basic		$	3.42		$	3.33
	– diluted		$	3.36		$	3.24
Bachman Group Companies [Member]	'
Schedule of Consolidated Income Statement Included Revenue and Earnings	'
	Included in the consolidated income statement of the Company since the acquisition date, are the following revenue and earnings for Bachman combined:
	(in millions)		Bachman
	Net sales		$	9.7
	Net income		$	0.3
Purchase Price and Fair Values of Assets Acquired and Liabilities Assumed	'
	The following table summarizes the calculations of the total purchase price and the estimated allocation of the purchase price to the assets acquired and liabilities assumed for Bachman. The purchase price allocation is not yet complete as we are in the process of finalising the valuation of the assets acquired. Final determination of the fair values may result in adjustments to the amounts presented below:
	(in millions)		Bachman
	Other intangible assets		$	25.9
	Goodwill			22.9
	Deferred tax on intangibles			(7.6	)
	Other net assets acquired, excluding cash of $2.0m			17.6
	Purchase price, net of cash acquired		$	58.8
Chemsil & Chemtec [Member]	'
Schedule of Consolidated Income Statement Included Revenue and Earnings	'
	Included in the consolidated income statement of the Company since the acquisition date, are the following revenue and earnings for Chemsil and Chemtec combined:
	(in millions)		Chemsil
			&
			Chemtec
	Net sales		$	11.8
	Net income		$	1
Purchase Price and Fair Values of Assets Acquired and Liabilities Assumed	'
	The following table summarizes the calculations of the total purchase price and the allocation of the purchase price to the assets acquired and liabilities assumed for Chemsil and Chemtec, which is now complete:
	(in millions)		Chemsil
			&
			Chemtec
	Other intangible assets		$	34
	Goodwill			16.7
	Other net assets, excluding cash of $1.3m			6.7
	Purchase price, net of cash acquired		$	57.4

Other_Intangible_Assets_Tables

Other Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2013
Goodwill And Intangible Assets Disclosure [Abstract]	'
Summary of Other Intangible Assets	'
	Other intangible assets comprise the following:
	(in millions)	2013			2012
	Gross cost:
	– Product rights	$	34		$	0
	– Brand names		2.9			0
	– Technology		33.9			25.4
	– Customer relationships		58.7			44.2
	– Patents		2.9			2.9
	– Internally developed software and other costs		19.5			10.1
	– Non-compete agreements		1.5			1.5
	– Marketing related		22.1			22.1
			175.5			106.2
	Accumulated amortization:
	– Product rights		(1.3	)		0
	– Brand names		(0.1	)		0
	– Technology		(7.9	)		(6.0	)
	– Customer relationships		(16.8	)		(12.7	)
	– Patents		(2.6	)		(2.3	)
	– Internally developed software and other costs		(1.0	)		0
	– Non-compete agreements		(0.7	)		0
	– Marketing related		(18.3	)		(16.6	)
			(48.7	)		(37.6	)
		$	126.8		$	68.6
Schedule of Future Amortization Estimated Expense	'
	Future amortization expense is estimated to be as follows for the next five years:
	(in millions)
	2014	$	16.6
	2015	$	16.6
	2016	$	16.6
	2017	$	16.6
	2018	$	14.3

Deferred_Finance_Costs_Tables

Deferred Finance Costs (Tables)	12 Months Ended
	Dec. 31, 2013
Text Block [Abstract]	'
Summary of Deferred Financing Cost	'
	(in millions)	2013			2012
	Gross cost	$	2.6		$	1.7
	Accumulated amortization		(0.8	)		(0.4	)
		$	1.8		$	1.3

Pension_Plans_Tables

Pension Plans (Tables)	12 Months Ended
	Dec. 31, 2013
United Kingdom Plan [Member]	'
Defined Benefit Pension Plan	'
	(in millions)	2013			2012			2011
	Plan net pension charge/(credit):
	Service cost	$	1.6		$	1.6		$	1.6
	Interest cost on PBO		31.3			32.2			36.6
	Expected return on plan assets		(35.5	)		(34.1	)		(36.7	)
	Amortization of prior service credit		(1.3	)		(1.3	)		(1.3	)
	Amortization of actuarial net losses		6.2			3.2			2.7
		$	2.3		$	1.6		$	2.9
	Plan assumptions at December 31, (%):
	Discount rate		4.4			4.15			4.75
	Inflation rate		2.55			2.2			2.15
	Rate of return on plan assets – overall on bid-value		4.85			4.9			4.85
	Rate of return on plan assets – equity securities		7.5			7.25			7.7
	Rate of return on plan assets – debt securities		3.4			3.65			3.6
	Plan asset allocation by category (%):
	Equity securities		35			33			29
	Debt securities		61			61			66
	Cash		4			6			5
			100			100			100
Movement in PBO and Fair Value of Plan Assets	'
	Movements in PBO and fair value of Plan assets are as follows:
	(in millions)	2013			2012
	Change in PBO:
	Opening balance	$	805.3		$	687.4
	Interest cost		31.3			32.2
	Service cost		1.6			1.6
	Benefits paid		(39.4	)		(43.9	)
	Actuarial losses/(gains)		5.9			94.4
	Exchange effect		15.1			33.6
	Closing balance	$	819.8		$	805.3
	Fair value of plan assets:
	Opening balance	$	768.6		$	708.8
	Actual benefits paid		(39.4	)		(43.9	)
	Actual contributions by employer		10.8			9.2
	Actual return on assets		35.5			61.2
	Exchange effect		14.8			33.3
	Closing balance	$	790.3		$	768.6
Fair Value of Pension Assets	'
	The fair values of pension assets by level of input were as follows:
	(in millions)	Quoted Prices			Significant			Significant			Total
		in Active			Other			Unobservable
		Markets for			Observable			Inputs
		Identical Assets			Inputs			(Level 3)
		(Level 1)			(Level 2)
	At December 31, 2013
	Fixed income securities:
	Debt securities issued by U.S. government and government agencies	$	1.3		$			$			$	1.3
	Debt securities issued by non-U.S. governments and government agencies		198.7									198.7
	Corporate debt securities		275.5									275.5
	Residential mortgage-backed securities		0.2									0.2
	Other asset-backed securities		3.8									3.8
	Equity securities:
	Equity securities held for proprietary investment purposes		156.7									156.7
	Real estate		61.4									61.4
	Other assets					25.3			38.3			63.6
	Total assets at fair value		697.6			25.3			38.3			761.2
	Cash		29.1									29.1
	Total plan assets	$	726.7		$	25.3		$	38.3		$	790.3
	At December 31, 2012
	Fixed income securities:
	Debt securities issued by U.S. government and government agencies	$	1.6		$			$			$	1.6
	Debt securities issued by non-U.S. governments and government agencies		191.3									191.3
	Corporate debt securities		284.6									284.6
	Residential mortgage-backed securities		0.2									0.2
	Other asset-backed securities		3.1									3.1
	Equity securities:
	Equity securities held for proprietary investment purposes		134.8									134.8
	Real estate		33.2									33.2
	Other assets					39			31			70
	Total assets at fair value		648.8			39			31			718.8
	Cash		49.8									49.8
	Total plan assets	$	698.6		$	39		$	31		$	768.6
Reconciliation of Fair Value of Plan Assets	'
	The reconciliation of the fair value of the Plan assets using significant unobservable inputs (Level 3) was as follows:
	(in millions)	Other
		Assets
	Balance at December 31, 2011	$	28.1
	Realized/unrealized gains/(losses):
	Relating to assets still held at the reporting date		1.3
	Relating to assets sold during the period		0
	Purchases, issuances and settlements		0.5
	Exchange effect		1.1
	Balance at December 31, 2012		31
	Realized/unrealized gains/(losses):
	Relating to assets still held at the reporting date		3.5
	Relating to assets sold during the period		0
	Purchases, issuances and settlements		3.6
	Exchange effect		0.2
	Balance at December 31, 2013	$	38.3
Plan Net Pension Charge	'
	The projected net pension charge for the year ending December 31, 2014 is as follows:
	(in millions)
	Service cost	$	1.7
	Interest cost on PBO		34.7
	Expected return on plan assets		(37.3	)
	Amortization of prior service credit		(1.3	)
	Amortization of actuarial net losses		5.5
		$	3.3
Expected Benefit Payments	'
	The following benefit payments are expected to be made:
	(in millions)
	2014	$	49.7
	2015	$	47
	2016	$	47.9
	2017	$	48.5
	2018	$	49.2
	2019 – 2023	$	258
German Plan [Member]	'
Movement in PBO and Fair Value of Plan Assets	'
	Movements in PBO of the German plan are as follows:
	(in millions)	2013			2012
	Change in PBO:
	Opening balance	$	9.3		$	6.3
	Service cost		0.2			0.1
	Interest cost		0.3			0.3
	Amortization of prior service cost/(credit)		(0.1	)		0
	Benefits paid		(0.2	)		(0.2	)
	Actuarial losses/(gains)		(0.4	)		2.6
	Exchange effect		0.5			0.2
	Closing balance	$	9.6		$	9.3
Unfunded Defined Benefit Pension Plan	'
	(in millions)	2013			2012			2011
	German plan net pension charge:
	Service cost	$	0.2		$	0.1		$	0.2
	Interest cost on PBO		0.3			0.3			0.3
	Amortization of prior service cost/(credit)		(0.1	)		0			0
	Amortization of actuarial net loss/(gain)		0.2			0			0
		$	0.6		$	0.4		$	0.5
	German plan assumptions (%):
	Discount rate		3.5			3.25			5
	Inflation rate		2			2			2
	Rate of increase in compensation levels		2.75			2.75			2.75

Income_Taxes_Tables

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2013
Income Tax Disclosure [Abstract]	'
Roll-Forward of Unrecognized Tax Benefits and Associated Accrued Interest and Penalties	'
	A roll-forward of unrecognized tax benefits and associated accrued interest and penalties is as follows:
	(in millions)	Interest and			Unrecognized			Total
		Penalties			Tax Benefits
	Opening balance at January 1, 2011	$	0.3		$	8.3		$	8.6
	Additions related to tax positions taken in the current period		0			5.2			5.2
	Additions for tax positions of prior periods		0.2			0.5			0.7
	Reductions for tax positions of prior periods		(0.1	)		(1.8	)		(1.9	)
	Closing balance at December 31, 2011		0.4			12.2			12.6
	Current		(0.3	)		(2.9	)		(3.2	)
	Non-current	$	0.1		$	9.3		$	9.4
	Opening balance at January 1, 2012	$	0.4		$	12.2		$	12.6
	Additions related to tax positions taken in the current period		0			0.2			0.2
	Additions for tax positions of prior periods		0.2			0			0.2
	Reductions due to lapsed statutes of limitations		0			(0.2	)		(0.2	)
	Closing balance at December 31, 2012		0.6			12.2			12.8
	Current		(0.3	)		(2.7	)		(3.0	)
	Non-current	$	0.3		$	9.5		$	9.8
	Opening balance at January 1, 2013	$	0.6		$	12.2		$	12.8
	Additions for tax positions of prior periods		0.6			0.2			0.8
	Reductions due to lapsed statutes of limitations		(0.1	)		(0.5	)		(0.6	)
	Closing balance at December 31, 2013		1.1			11.9			13
	Current		(0.6	)		(6.2	)		(6.8	)
	Non-current	$	0.5		$	5.7		$	6.2
Sources of Income Before Income Taxes	'
	The sources of income before income taxes were as follows:
	(in millions)	2013			2012			2011
	Domestic	$	10		$	5.6		$	(42.6	)
	Foreign		82.8			87.7			92.8
		$	92.8		$	93.3		$	50.2
Components of Income Tax Charges	'
	The components of income tax charges are summarized as follows:
	(in millions)	2013			2012			2011
	Current:
	Federal	$	1.6		$	2.9		$	5.4
	Foreign		6.8			11.8			13.6
			8.4			14.7			19
	Deferred:
	Federal		1.8			12.3			(12.8	)
	Foreign		4.8			(0.6	)		(3.1	)
			6.6			11.7			(15.9	)
		$	15		$	26.4		$	3.1
Factors Effecting Effective Tax Rate from U.S. Federal Statutory Rate	'
	The effective tax rate varies from the U.S. federal statutory rate because of the factors indicated below:
		2013			2012			2011
	Statutory rate		35	%		35	%		35	%
	Foreign income inclusions		6.1			48.9			20.5
	Impairment of Octane Additives segment goodwill		0.5			0.5			1.3
	Foreign tax credits		(1.9	)		(38.3	)		(25.8	)
	Pension (credit)/charge		(0.3	)		(0.3	)		(9.7	)
	Foreign tax rate differential		(14.6	)		(16.4	)		(19.1	)
	Permanent tax adjustments		(2.5	)		(0.2	)		0.3
	Amortization		1.1			0.5			0.7
	Tax (credit)/charge from previous years		(2.9	)		(0.6	)		(1.9	)
	Net charge/(credit) from unrecognized tax benefits		0.2			0.3			7.7
	United Kingdom income tax rate reduction		0.9			(0.6	)		(4.8	)
	Other items and adjustments, net		(5.4	)		(0.5	)		2
			16.2	%		28.3	%		6.2	%
Details of Deferred Tax Assets and Liabilities	'
	Details of deferred tax assets and liabilities are analyzed as follows:
	(in millions)	2013			2012
	Deferred tax assets:
	Foreign tax credits	$	4.5		$	5.5
	Accrued expenses		3.4			4.6
	Stock options		5.2			5.5
	Excess of tax over book basis in property, plant and equipment		0.9			1.1
	Net operating loss carry forwards		0.3			0.3
	Pension liabilities		6.5			9.2
	Other intangible assets		1			0
	Other		3.9			4.7
	Valuation allowance		0			0
	Deferred tax liabilities:
	Goodwill amortization		(7.2	)		(6.9	)
	Other intangible assets		(0.3	)		(0.9	)
	Excess of book over tax basis in tax deductible goodwill		(0.2	)		0
	Excess of book over tax basis in intangible assets		(7.5	)		0
	Other		(2.9	)		(3.2	)
	Total net deferred tax asset	$	7.6		$	19.9
	Deferred taxes are included within the consolidated balance sheets as follows:
	Deferred tax assets	$	17.3		$	23.7
	Deferred tax liabilities		(9.7	)		(3.8	)
		$	7.6		$	19.9
	Current portion of deferred tax assets	$	8.7		$	11
	Deferred tax assets, net of current portion		8.6			12.7
	Current portion of deferred tax liabilities		(0.2	)		(0.2	)
	Deferred tax liabilities, net of current portion		(9.5	)		(3.6	)
		$	7.6		$	19.9
Details of Deferred Tax Asset Valuation Allowance	'
	Details of the deferred tax asset valuation allowance are as follows:
	(in millions)	2013			2012			2011
	At January 1	$	0		$	(7.5	)	$	(10.8	)
	Change in foreign tax credits		0			7.5			3.3
	At December 31	$	0		$	0		$	(7.5	)

LongTerm_Debt_Tables

Long-Term Debt (Tables)	12 Months Ended
	Dec. 31, 2013
Debt Disclosure [Abstract]	'
Schedule of Long-Term Debt	'
	Long-term debt consists of the following:
	(in millions)	2013			2012
	Revolving credit facility	$	142		$	20
	Promissory note		5			10
	Other long-term debt		1			0
			148			30
	Less current portion		(5.3	)		(5.0	)
		$	142.7		$	25

Plant_Closure_Provisions_Table

Plant Closure Provisions (Tables)	12 Months Ended
	Dec. 31, 2013
Restructuring And Related Activities [Abstract]	'
Movements in Plant Closure and Restructuring Provisions	'
	Movements in the provisions are summarized as follows:
	(in millions)	Severance			Other			Remediation			Total
					Restructuring
	Total at January 1, 2011	$	1.5		$	0.1		$	25.9		$	27.5
	Charge for the period		0.7			(0.1	)		4.5			5.1
	Utilized in the period		(0.7	)		0			(3.1	)		(3.8	)
	Exchange effect		0			0			(0.2	)		(0.2	)
	Total at December 31, 2011		1.5			0			27.1			28.6
	Due within one year		(0.5	)		0			(3.6	)		(4.1	)
	Due after one year	$	1		$	0		$	23.5		$	24.5
	Total at January 1, 2012	$	1.5		$	0		$	27.1		$	28.6
	Charge for the period		0.2			0			4			4.2
	Utilized in the period		(0.6	)		0			(2.1	)		(2.7	)
	Exchange effect		0			0			0.3			0.3
	Total at December 31, 2012		1.1			0			29.3			30.4
	Due within one year		(0.1	)		0			(5.0	)		(5.1	)
	Due after one year	$	1		$	0		$	24.3		$	25.3
	Total at January 1, 2013	$	1.1			0			29.3			30.4
	Charge for the period		0			0			3.9			3.9
	Utilized in the period		(0.1	)		0			(1.9	)		(2.0	)
	Exchange effect		0			0			0.1			0.1
	Total at December 31, 2013		1			0			31.4			32.4
	Due within one year		0			0			(6.2	)		(6.2	)
	Due after one year	$	1		$	0		$	25.2		$	26.2

Deferred_Income_Tables

Deferred Income (Tables)	12 Months Ended
	Dec. 31, 2013
Revenue Recognition [Abstract]	'
Summary of Deferred Income	'
	Deferred income consists of:
	(in millions)	2013			2012
	Deferred income	$	1.5		$	2.3
	Less current portion		(0.3	)		(1.4	)
	Non-current deferred income	$	1.2		$	0.9

Profit_on_Disposal_Net_Tables

Profit on Disposal, Net (Tables)	12 Months Ended
	Dec. 31, 2013
Other Income And Expenses [Abstract]	'
Summary of Profit on Disposal, Net	'
	(in millions)	2013		2012		2011
	Profit on disposal of surplus United Kingdom real estate	$	0	$	0.1	$	0
	Loss on disposal of surplus U.S. real estate		0		0		0
		$	0	$	0.1	$	0

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2013
Fair Value Disclosures [Abstract]	'
Carrying Amount and Fair Values of the Company's Assets and Liabilities Measured on a Recurring Basis	'
	The following table presents the carrying amount and fair values of the Company’s assets and liabilities measured on a recurring basis:
		December 31,					December 31,
		2013					2012
	(in millions)	Carrying			Fair		Carrying		Fair
		Amount			Value		Amount		Value
	Assets
	Non-derivatives:
	Cash and cash equivalents	$	80.2		$	80.2	$	22.4	$	22.4
	Short-term investments		6.6			6.6		5.1		5.1
	Non-financial assets (Level 3 measurement):
	Goodwill – Octane Additives		0			0		1.3		1.3
	Derivatives (Level 1 measurement):
	Other non-current assets:
	Commodity swaps		0			0		0.1		0.1
	Foreign currency forward exchange contracts		1			1		0.8		0.8
	Liabilities
	Non-derivatives:
	Long-term debt (including current portion)	$	148		$	148	$	30	$	30
	Non-financial liabilities (Level 3 measurement):
	Stock equivalent units		12.1			12.1		12.6		12.6
	Acquisition-related contingent consideration		4.6			4.6		4.3		4.3
Summary of Cumulative Gains and Losses on the Interest Rate Swaps and Commodity Swaps	'
	The cumulative gains and losses on the interest rate swaps and commodity swaps are summarized as follows:
	(in millions)	2013			2012
	Balance at January 1	$	0.1		$	0.1
	Change in fair value		(0.1	)		0
	Balance at December 31	$	0		$	0.1

Derivative_Instruments_and_Ris1

Derivative Instruments and Risk Management (Tables)

12 Months Ended

Dec. 31, 2013

Derivative Instruments And Hedging Activities Disclosure [Abstract]

'

Summary of Commodity Swaps

'

The Company has hedged the cost of certain raw materials with commodity swaps which are summarized as follows:

December 31,

December 31,

2013

2012

(in millions)

Carrying

Fair

Carrying

Fair

Amount

Value

Amount

Value

Notional quantity – 275 tonnes

$

0.1

$

0.1

Notional quantity – 0 tonnes

$

0

$

0

Summary of Foreign Currency Forward Exchange Contracts Which Have Not Been Designated as Hedging Instruments, and Their Impact on Income Statement

'

These foreign currency forward exchange contracts have not been designated as hedging instruments, and their impact on the income statement in 2013, 2012 and 2011 is summarized below:

Location of Gain/(Loss)

Amount of Gain/(Loss)

Recognized in Income

Recognized in Income

(in millions)

2013

2012

2011

Foreign currency forward exchange contracts

Other income/(expense)

$

(1.5

)

$

1.2

$

1.3

Commitments_and_Contingencies_

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2013
Commitments And Contingencies Disclosure [Abstract]	'
Future Commitments Under Non-Cancelable Operating Leases	'
	Future commitments under non-cancelable operating leases are as follows:
	(in millions)
	2014	$	2.7
	2015		2.6
	2016		2.3
	2017		1.9
	2018		1.7
	Thereafter		2.9
		$	14.1
Schedule of Expected Settlement Payment	'
	The settlement consists of fines, penalties and disgorgements which are payable over a period of four years commencing 2010. As at December 31, 2013, the expected schedule of payments was as follows:
	(in millions)	Government			Compliance			Total
		Authorities			Monitor
	Fines, penalties and disgorgements	$	40.2		$	0		$	40.2
	Fees and associated expenses		0			3.9			3.9
	Less discounting to fair value		0			0			0
			40.2			3.9			44.1
	Amounts paid		(40.2	)		(3.6	)		(43.8	)
	Exchange effect		0			0			0
			0			0.3			0.3
	Due within one year		0			(0.3	)		(0.3	)
		$	0		$	0		$	0

Stockholders_Equity_Tables

Stockholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2013
Equity [Abstract]	'
Stockholders' Equity	'
		Common Stock						Treasury Stock
	(number of shares in thousands)	2013		2012		2011		2013			2012			2011
	At January 1		29,555		29,555		29,555		6,222			6,507			5,851
	Exercise of options		0		0		0		(632	)		(333	)		(236	)
	Acquisition-related stock issued		0		0		0		(471	)		0			0
	Stock purchases		0		0		0		89			48			1,087
	Settlement of NewMarket		0		0		0		0			0			(195	)
	Corporation civil complaint
	At December 31		29,555		29,555		29,555		5,208			6,222			6,507

StockBased_Compensation_Plans_

Stock-Based Compensation Plans (Tables)	12 Months Ended
	Dec. 31, 2013
Fair Value of Liability Cash-Settled Stock Appreciation Rights	'
	The fair value of these liability cash-settled stock appreciation rights was calculated on a quarterly basis using a Monte Carlo model and is summarized as follows:
	(in millions)	2013			2012			2011
	Balance at January 1	$	1.3		$	2.2		$	0.8
	Compensation charge		0			5.8			1.4
	Cash paid		(1.3	)		(6.7	)		0
	Balance at December 31	$	0		$	1.3		$	2.2
Long Term Incentive Plan [Member]	'
Assumptions Used in the Monte Carlo Model	'
	The following assumptions were used in the Monte Carlo model:
		2012			2011
	Dividend yield		0	%		0	%
	Volatility		0	%		53.5	%
	Risk free interest rate		0.36	%		0.36	%
Stock Option Plan [Member]	'
Assumptions Used to Determine Grant-Date Fair Value of Options	'
	The following weighted average assumptions were used to determine the grant-date fair value of options:
		2013			2012			2011
	Dividend yield		0.11	%		0	%		0.2	%
	Expected life		5 years			5 years			5 years
	Volatility		41.1	%		60.1	%		78.3	%
	Risk free interest rate		0.46	%		0.43	%		1.22	%
Summary of Transactions of the Company's Stock Option Plans	'
	The following table summarizes the transactions of the Company’s stock option plans for the year ended December 31, 2013:
		Number of			Weighted			Weighted
		Options			Average			Average
					Exercise Price			Grant-Date
								Fair Value
	Outstanding at December 31, 2012		1,001,241		$	6.27
	Granted – at discount		78,828		$	0		$	36.3
	– at market value		22,161		$	41.27		$	16.09
	Exercised		(629,152	)	$	5.96
	Forfeited		(25,688	)	$	6.21
	Outstanding at December 31, 2013		447,390		$	7.33
Stock Equivalent Units [Member]	'
Assumptions Used to Determine Fair Value of SEUs	'
	The following assumptions were used to determine the fair value of SEUs at the balance sheet dates:
		2013			2012			2011
	Dividend yield		1.08	%		0	%		0	%
	Volatility		37.61	%		43.8	%		64.2	%
	Risk free interest rate		0.78	%		0.36	%		0.36	%
Summarizes the Transactions of the SEUs	'
	The following table summarizes the transactions of the Company’s SEUs for the year ended December 31, 2013:
		Number			Weighted			Weighted
		of SEUs			Average			Average
					Exercise Price			Grant-Date
								Fair Value
	Outstanding at December 31, 2012		623,828		$	2.95
	Granted – at discount		59,028		$	0		$	35.29
	– at market value		6,970		$	41.31		$	16.09
	Exercised		(281,703	)	$	2.25
	Forfeited		(4,861	)	$	5.04
	Outstanding at December 31, 2013		403,262		$	3.64

Reclassifications_Out_of_Accum1

Reclassifications Out of Accumulated Other Comprehensive Income/(Loss) (Tables)	12 Months Ended
	Dec. 31, 2013
Text Block [Abstract]	'
Summary of Reclassifications Out of Accumulated Other Comprehensive Loss	'
	Reclassifications out of accumulated other comprehensive loss for 2013 were:
	(in millions)		Amount			Affected Line Item in the
			Reclassified			Statement where
	Details about AOCL Components		from AOCL			Net Income is Presented
	Derivative instruments:
	Realized gain/(loss) on derivative instruments		$	(0.1	)	Cost of goods sold
				(0.1	)	Total before tax
				0		Income tax expense
			$	(0.1	)	Net of tax
	Defined benefit pension plan items:
	Amortization of prior service credit		$	(1.3	)	See (¹) below
	Amortization of actuarial net losses			6.2		See (¹) below
				4.9		Total before tax
				(1.1	)	Income tax expense
				3.8		Net of tax
	Total reclassifications		$	3.7		Net of tax
	-1	These items are included in the computation of net periodic pension cost. See Note 9 for additional information.
Changes in Accumulated Other Comprehensive Loss	'
	Changes in accumulated other comprehensive loss for 2013, net of tax, were:
	(in millions)		Unrealized			Defined			Cumulative			Total
			Gains/			Benefit			Translation
			(Losses) on			Pension			Adjustments
			Derivative			Plan Items
			Instruments
	Balance at December 31, 2012		$	0.1		$	(117.3	)	$	(34.9	)	$	(152.1	)
	Other comprehensive income/(loss) before reclassifications			0			0			1.2			1.2
	Actuarial net losses arising during the year						(6.7	)					(6.7	)
	Amounts reclassified from AOCL			(0.1	)		3.8			0			3.7
	Net current period other comprehensive income/(loss)			(0.1	)		(2.9	)		1.2			(1.8	)
	Balance at December 31, 2013		$	0		$	(120.2	)	$	(33.7	)	$	(153.9	)

Accounting_Policies_Additional

Accounting Policies - Additional Information (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Accounting Policies [Line Items]	'	'	'	'
Non-cash pension expense, net of tax	'	$1.40	$1.80	$16.10
Impairment of goodwill	1.3	1.2	2	'
Minimum [Member]	'	'	'	'
Accounting Policies [Line Items]	'	'	'	'
Short-term investments maturity period	'3 months	'	'	'
Maximum [Member]	'	'	'	'
Accounting Policies [Line Items]	'	'	'	'
Cash equivalents maturity period	'3 months	'	'	'
Short-term investments maturity period	'12 months	'	'	'
Fuel Specialties [Member]	'	'	'	'
Accounting Policies [Line Items]	'	'	'	'
Impairment of goodwill	0	0	'	'
Performance Chemicals [Member]	'	'	'	'
Accounting Policies [Line Items]	'	'	'	'
Impairment of goodwill	$0	$0	'	'

Accounting_Policies_Revision_o

Accounting Policies - Revision of Prior Year Adjustments (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Change in Accounting Estimate [Line Items]	'	'	'	'
Selling, general and administrative expenses	($141.90)	($119)	($158.30)	'
Operating income	90.6	96.5	47.2	'
Income before income taxes	92.8	93.3	50.2	'
Income taxes	-15	-26.4	-3.1	'
Net income	77.8	66.9	47.1	'
Retained earnings	327.5	261.7	241.5	194.4
Accumulated other comprehensive loss	-153.9	-152.1	-102.1	-115.5
As Previously Reported [Member]	'	'	'	'
Change in Accounting Estimate [Line Items]	'	'	'	'
Selling, general and administrative expenses	'	-117.1	-155.9	'
Operating income	'	98.4	49.6	'
Income before income taxes	'	95.2	52.6	'
Income taxes	'	-26.9	-3.7	'
Net income	'	68.3	48.9	'
Retained earnings	'	281	259.4	210.5
Accumulated other comprehensive loss	'	-171.4	-120	-131.6
Adjustment [Member]	'	'	'	'
Change in Accounting Estimate [Line Items]	'	'	'	'
Selling, general and administrative expenses	'	-1.9	-2.4	'
Operating income	'	-1.9	-2.4	'
Income before income taxes	'	-1.9	-2.4	'
Income taxes	'	0.5	0.6	'
Net income	'	-1.4	-1.8	'
Retained earnings	'	-19.3	-17.9	-16.1
Accumulated other comprehensive loss	'	$19.30	$17.90	$16.10

Accounting_Policies_Estimated_

Accounting Policies - Estimated Useful Lives of Major Classes of Depreciable Assets (Detail)	12 Months Ended
	Dec. 31, 2013
Buildings [Member] | Minimum [Member]	'
Property, Plant and Equipment [Line Items]	'
Estimated useful lives of assets	'7 years
Buildings [Member] | Maximum [Member]	'
Property, Plant and Equipment [Line Items]	'
Estimated useful lives of assets	'25 years
Equipment [Member] | Minimum [Member]	'
Property, Plant and Equipment [Line Items]	'
Estimated useful lives of assets	'3 years
Equipment [Member] | Maximum [Member]	'
Property, Plant and Equipment [Line Items]	'
Estimated useful lives of assets	'10 years

Segmental_Reporting_and_Geogra2

Segmental Reporting and Geographical Area Data - Additional Information (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Segment Reporting Information [Line Items]	'	'	'
Number of segments	3	'	'
Shell [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Amount of net group sales	$83.10	$82.90	$78.70
Sales [Member] | Shell [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Percentage of net group sales	10.00%	11.00%	10.00%

Segmental_Reporting_and_Geogra3

Segmental Reporting and Geographical Area Data - Segment Reporting (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Segment Reporting Information [Line Items]	'	'	'
Net sales	$818.80	$776.40	$774.40
Gross profit	255.2	236.4	226.4
Operating income	90.6	96.5	47.2
Identifiable assets at year end	794.7	579.4	568.8
Restructuring charge	-0.2	-0.2	-0.6
Impairment of Octane Additives segment goodwill	-1.3	-1.2	-2
Profit on disposal, net	0	0.1	0
Fuel Specialties [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Identifiable assets at year end	446.4	356.6	281.5
Impairment of Octane Additives segment goodwill	0	0	'
Performance Chemicals [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Identifiable assets at year end	176.8	113.4	106.7
Impairment of Octane Additives segment goodwill	0	0	'
Octane Additives [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Identifiable assets at year end	42	48.9	51.5
Impairment of Octane Additives segment goodwill	-1.3	-1.2	-2
Operating Segments [Member] | Fuel Specialties [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Net sales	567.4	527.2	521.2
Gross profit	181.1	158.7	149.3
Operating income	92.7	87.6	81.7
Operating Segments [Member] | Performance Chemicals [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Net sales	192.4	179.6	177
Gross profit	46.3	43.8	40.6
Operating income	23.6	24.3	22.6
Operating Segments [Member] | Octane Additives [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Net sales	59	69.6	76.2
Gross profit	27.8	33.9	36.5
Operating income	21.5	26	-22.4
Segment Reconciling Items [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Pension credit/(charge)	-2.3	-1.6	-2.9
Restructuring charge	-0.2	-0.2	-0.6
Impairment of Octane Additives segment goodwill	-1.3	-1.2	-2
Profit on disposal, net	0	0.1	0
Corporate, Non-Segment [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Identifiable assets at year end	128.8	60.5	129.1
Corporate costs	($43.40)	($38.50)	($29.20)

Segmental_Reporting_and_Geogra4

Segmental Reporting and Geographical Area Data - Segment Reporting on Basis of Geographical Location (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Revenues from External Customers and Long-Lived Assets [Line Items]	'	'	'
Net sales	$818.80	$776.40	$774.40
Income before income taxes	92.8	93.3	50.2
Long-lived assets at year end	189.1	71.7	65.3
Identifiable assets at year end	794.7	579.4	568.8
United States [Member]	'	'	'
Revenues from External Customers and Long-Lived Assets [Line Items]	'	'	'
Income before income taxes	10	5.6	-42.6
Long-lived assets at year end	148.2	31.5	22
Identifiable assets at year end	291	174.1	123.2
United Kingdom [Member]	'	'	'
Revenues from External Customers and Long-Lived Assets [Line Items]	'	'	'
Income before income taxes	43.7	36.3	36.6
Long-lived assets at year end	29.4	28.7	32.4
Identifiable assets at year end	261.5	192.1	253.8
Rest of Europe [Member]	'	'	'
Revenues from External Customers and Long-Lived Assets [Line Items]	'	'	'
Income before income taxes	40.4	52.6	58.2
Long-lived assets at year end	11.5	11.5	10.9
Identifiable assets at year end	53.2	63.8	49.8
Other [Member]	'	'	'
Revenues from External Customers and Long-Lived Assets [Line Items]	'	'	'
Identifiable assets at year end	0.4	0.4	0.5
Octane Additives [Member]	'	'	'
Revenues from External Customers and Long-Lived Assets [Line Items]	'	'	'
Income before income taxes	-1.3	-1.2	-2
Identifiable assets at year end	42	48.9	51.5
Goodwill [Member]	'	'	'
Revenues from External Customers and Long-Lived Assets [Line Items]	'	'	'
Identifiable assets at year end	187.9	149	141.5
Sales by Source [Member]	'	'	'
Revenues from External Customers and Long-Lived Assets [Line Items]	'	'	'
Net sales	818.8	776.4	774.4
Sales by Source [Member] | United States [Member]	'	'	'
Revenues from External Customers and Long-Lived Assets [Line Items]	'	'	'
Net sales	276.1	274.1	265.6
Sales by Source [Member] | United Kingdom [Member]	'	'	'
Revenues from External Customers and Long-Lived Assets [Line Items]	'	'	'
Net sales	502.4	475.1	482.8
Sales by Source [Member] | Rest of Europe [Member]	'	'	'
Revenues from External Customers and Long-Lived Assets [Line Items]	'	'	'
Net sales	129.1	142.8	151.7
Sales by Source [Member] | Other [Member]	'	'	'
Revenues from External Customers and Long-Lived Assets [Line Items]	'	'	'
Net sales	0.2	0.5	0.9
Sales by Source [Member] | Sales Between Areas [Member]	'	'	'
Revenues from External Customers and Long-Lived Assets [Line Items]	'	'	'
Net sales	-89	-116.1	-126.6
Sales by Destination [Member]	'	'	'
Revenues from External Customers and Long-Lived Assets [Line Items]	'	'	'
Net sales	818.8	776.4	774.4
Sales by Destination [Member] | United States [Member]	'	'	'
Revenues from External Customers and Long-Lived Assets [Line Items]	'	'	'
Net sales	278.7	272.4	248.2
Sales by Destination [Member] | United Kingdom [Member]	'	'	'
Revenues from External Customers and Long-Lived Assets [Line Items]	'	'	'
Net sales	30	38.8	48.5
Sales by Destination [Member] | Rest of Europe [Member]	'	'	'
Revenues from External Customers and Long-Lived Assets [Line Items]	'	'	'
Net sales	325.5	331	304.2
Sales by Destination [Member] | Other [Member]	'	'	'
Revenues from External Customers and Long-Lived Assets [Line Items]	'	'	'
Net sales	$184.60	$134.20	$173.50

Earnings_Per_Share_Summary_of_

Earnings Per Share - Summary of Earnings Per Share (Detail) (USD $)	12 Months Ended
In Millions, except Share data in Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Numerator (in millions):	'	'	'
Net income available to common stockholders	$77.80	$66.90	$47.10
Denominator (in thousands):	'	'	'
Weighted average common shares outstanding	23,651	23,187	23,568
Dilutive effect of stock options and awards	505	663	952
Denominator for diluted earnings per share	24,156	23,850	24,520
Net income per share, basic:	$3.29	$2.89	$2
Net income per share, diluted:	$3.22	$2.81	$1.92

Earnings_Per_Share_Additional_

Earnings Per Share - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Earnings Per Share [Abstract]	'	'	'
Average number of anti-dilutive options excluded from the calculation of diluted earnings per share	'	1,380	690

Property_Plant_and_Equipment_S

Property, Plant and Equipment - Schedule of Property, Plant and Equipment (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Property, Plant and Equipment [Line Items]	'	'
Property, plant and equipment, Gross	$175.10	$146.20
Less accumulated depreciation	-114.7	-96.4
Property, plant and equipment, Net	60.4	49.8
Land [Member]	'	'
Property, Plant and Equipment [Line Items]	'	'
Property, plant and equipment, Gross	7.5	7.2
Buildings [Member]	'	'
Property, Plant and Equipment [Line Items]	'	'
Property, plant and equipment, Gross	10.8	6.5
Equipment [Member]	'	'
Property, Plant and Equipment [Line Items]	'	'
Property, plant and equipment, Gross	152.9	129
Work in Progress [Member]	'	'
Property, Plant and Equipment [Line Items]	'	'
Property, plant and equipment, Gross	$3.90	$3.50

Property_Plant_and_Equipment_A

Property, Plant and Equipment - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Property Plant And Equipment [Abstract]	'	'	'
Amount of assets held under capital leases	$0	$0	$0
Depreciation charges	8,900,000	7,000,000	9,200,000
Estimated additional cost to complete work in progress	$2,200,000	$2,700,000	'

Goodwill_Summary_of_Goodwill_D

Goodwill - Summary of Goodwill (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Goodwill [Line Items]	'	'	'
At January 1, Gross cost	$384.20	$375.50	'
At January 1, Accumulated impairment losses	-235.2	-234	'
At January 1, Net book amount	149	141.5	'
Exchange effect	0	0	'
Acquisitions	39.6	8.7	'
Adjustments to purchase price allocation	0.6	'	'
Impairment losses	-1.3	-1.2	-2
At December 31, Gross cost	424.4	384.2	375.5
At December 31, Accumulated impairment losses	-236.5	-235.2	-234
At December 31, Net book amount	187.9	149	141.5
Fuel Specialties [Member]	'	'	'
Goodwill [Line Items]	'	'	'
At January 1, Gross cost	117.6	108.8	'
At January 1, Accumulated impairment losses	0	0	'
At January 1, Net book amount	117.6	108.8	'
Exchange effect	0	0.1	'
Acquisitions	22.9	8.7	'
Adjustments to purchase price allocation	0.6	'	'
Impairment losses	0	0	'
At December 31, Gross cost	141.1	117.6	'
At December 31, Accumulated impairment losses	0	0	'
At December 31, Net book amount	141.1	117.6	'
Performance Chemicals [Member]	'	'	'
Goodwill [Line Items]	'	'	'
At January 1, Gross cost	30.1	30.1	'
At January 1, Accumulated impairment losses	0	0	'
At January 1, Net book amount	30.1	30.1	'
Exchange effect	0	0	'
Acquisitions	16.7	0	'
Adjustments to purchase price allocation	0	'	'
Impairment losses	0	0	'
At December 31, Gross cost	46.8	30.1	'
At December 31, Accumulated impairment losses	0	0	'
At December 31, Net book amount	46.8	30.1	'
Octane Additives [Member]	'	'	'
Goodwill [Line Items]	'	'	'
At January 1, Gross cost	236.5	236.6	'
At January 1, Accumulated impairment losses	-235.2	-234	'
At January 1, Net book amount	1.3	2.6	'
Exchange effect	0	-0.1	'
Acquisitions	0	0	'
Adjustments to purchase price allocation	0	'	'
Impairment losses	-1.3	-1.2	-2
At December 31, Gross cost	236.5	236.5	236.6
At December 31, Accumulated impairment losses	-236.5	-235.2	-234
At December 31, Net book amount	$0	$1.30	$2.60

Goodwill_Summary_of_Goodwill_P

Goodwill - Summary of Goodwill (Parenthetical) (Detail) (USD $)	Dec. 31, 2013
In Millions, unless otherwise specified
Fuel Specialties [Member]	'
Goodwill [Line Items]	'
Historical accumulated amortization	$8.70
Performance Chemicals [Member]	'
Goodwill [Line Items]	'
Historical accumulated amortization	0.3
Octane Additives [Member]	'
Goodwill [Line Items]	'
Historical accumulated amortization	$289.50

Goodwill_Additional_Informatio

Goodwill - Additional Information (Detail) (USD $)

12 Months Ended

12 Months Ended

12 Months Ended

12 Months Ended

In Millions, except Share data, unless otherwise specified

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Dec. 31, 2013

Aug. 30, 2013

Dec. 31, 2013

Dec. 31, 2013

Nov. 04, 2013

Octane Additives [Member]

Octane Additives [Member]

Octane Additives [Member]

Fuel Specialties [Member]

Fuel Specialties [Member]

Fuel Specialties [Member]

Performance Chemicals [Member]

Performance Chemicals [Member]

Performance Chemicals [Member]

Chemsil & Chemtec [Member]

Chemsil & Chemtec [Member]

Strata [Member]

Bachman Group Companies [Member]

Bachman Group Companies [Member]

Goodwill [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Impairment of goodwill

$1.30

$1.20

$2

$1.30

$1.20

$2

$0

$0

'

$0

$0

'

'

'

'

'

'

Goodwill

187.9

149

141.5

0

1.3

2.6

141.1

117.6

108.8

46.8

30.1

30.1

16.7

'

'

22.9

'

Voting equity interests acquired

'

'

'

'

'

'

'

'

'

'

'

'

'

100.00%

'

'

100.00%

Purchase price of cash

51.2

'

'

'

'

'

'

'

'

'

'

'

'

'

'

45.8

'

Issuance of common stock

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

319,953

'

Purchase price of common stock

6.2

'

'

'

'

'

'

'

'

'

'

'

'

'

'

15

'

Date of acquisition

'

'

'

'

'

'

'

'

'

'

'

'

30-Aug-13

'

'

4-Nov-13

'

Reduction in other net assets

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$0.60

'

'

Goodwill_Schedule_of_Consolida

Goodwill - Schedule of Consolidated Income Statement Included Revenue and Earnings (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Business Acquisition [Line Items]	'	'	'
Net sales	$818.80	$776.40	$774.40
Net income	77.8	66.9	47.1
Bachman Group Companies [Member]	'	'	'
Business Acquisition [Line Items]	'	'	'
Net sales	9.7	'	'
Net income	0.3	'	'
Chemsil & Chemtec [Member]	'	'	'
Business Acquisition [Line Items]	'	'	'
Net sales	11.8	'	'
Net income	$1	'	'

Goodwill_Purchase_Price_and_Fa

Goodwill - Purchase Price and Fair Values of Assets Acquired and Liabilities Assumed (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
In Millions, unless otherwise specified
Business Acquisition [Line Items]	'	'	'
Goodwill	$187.90	$149	$141.50
Bachman Group Companies [Member]	'	'	'
Business Acquisition [Line Items]	'	'	'
Other intangible assets	25.9	'	'
Goodwill	22.9	'	'
Deferred tax on intangibles	-7.6	'	'
Other net assets acquired	17.6	'	'
Purchase price, net of cash acquired	58.8	'	'
Chemsil & Chemtec [Member]	'	'	'
Business Acquisition [Line Items]	'	'	'
Other intangible assets	34	'	'
Goodwill	16.7	'	'
Other net assets acquired	6.7	'	'
Purchase price, net of cash acquired	$57.40	'	'

Goodwill_Purchase_Price_and_Fa1

Goodwill - Purchase Price and Fair Values of Assets Acquired and Liabilities Assumed (Parenthetical) (Detail) (USD $)	Dec. 31, 2013
In Millions, unless otherwise specified
Bachman Group Companies [Member]	'
Business Acquisition [Line Items]	'
Cash acquired	$2
Chemsil & Chemtec [Member]	'
Business Acquisition [Line Items]	'
Cash acquired	$1.30

Goodwill_Schedule_of_Pro_Forma

Goodwill - Schedule of Pro Forma Financial Information (Detail) (USD $)	12 Months Ended
In Millions, except Per Share data, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Goodwill And Intangible Assets Disclosure [Abstract]	'	'
Net sales	$913.10	$904.60
Net income	$85.10	$77.20
Earnings per share - basic	$3.42	$3.33
Earnings per share - diluted	$3.36	$3.24

Other_Intangible_Assets_Summar

Other Intangible Assets - Summary of Other Intangible Assets (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012	Jun. 30, 2007
In Millions, unless otherwise specified
Finite-Lived Intangible Assets [Line Items]	'	'	'
Gross cost	$175.50	$106.20	'
Accumulated amortization	-48.7	-37.6	'
Other Intangible Assets, Net	126.8	68.6	'
Product Rights [Member]	'	'	'
Finite-Lived Intangible Assets [Line Items]	'	'	'
Gross cost	34	0	'
Accumulated amortization	-1.3	0	'
Brand Names [Member]	'	'	'
Finite-Lived Intangible Assets [Line Items]	'	'	'
Gross cost	2.9	0	'
Accumulated amortization	-0.1	0	'
Technology [Member]	'	'	'
Finite-Lived Intangible Assets [Line Items]	'	'	'
Gross cost	33.9	25.4	'
Accumulated amortization	-7.9	-6	'
Customer Relationships [Member]	'	'	'
Finite-Lived Intangible Assets [Line Items]	'	'	'
Gross cost	58.7	44.2	'
Accumulated amortization	-16.8	-12.7	'
Patents [Member]	'	'	'
Finite-Lived Intangible Assets [Line Items]	'	'	'
Gross cost	2.9	2.9	'
Accumulated amortization	-2.6	-2.3	'
Internally Developed Software and Other Costs [Member]	'	'	'
Finite-Lived Intangible Assets [Line Items]	'	'	'
Gross cost	19.5	10.1	'
Accumulated amortization	-1	0	'
Non-Compete Agreements [Member]	'	'	'
Finite-Lived Intangible Assets [Line Items]	'	'	'
Gross cost	1.5	1.5	'
Accumulated amortization	-0.7	0	'
Marketing Related [Member]	'	'	'
Finite-Lived Intangible Assets [Line Items]	'	'	'
Gross cost	22.1	22.1	28.4
Accumulated amortization	($18.30)	($16.60)	'

Other_Intangible_Assets_Additi

Other Intangible Assets - Additional Information (Detail) (USD $)

12 Months Ended

12 Months Ended

12 Months Ended

12 Months Ended

12 Months Ended

12 Months Ended

12 Months Ended

12 Months Ended

12 Months Ended

In Millions, unless otherwise specified

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2008

Jun. 30, 2007

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2012

Nov. 04, 2013

Dec. 31, 2013

Nov. 04, 2013

Dec. 31, 2013

Nov. 04, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2012

Aug. 30, 2013

Brand Names [Member]

Brand Names [Member]

Technology [Member]

Technology [Member]

Customer Relationships [Member]

Customer Relationships [Member]

Customer Lists [Member]

Patents [Member]

Patents [Member]

Internally Developed Software and Other Costs [Member]

Internally Developed Software and Other Costs [Member]

Internally Developed Software and Other Costs [Member]

Internally Developed Software and Other Costs [Member]

Non-Compete Agreements [Member]

Non-Compete Agreements [Member]

Non-Compete Agreements [Member]

Non-Compete Agreements [Member]

Marketing Related [Member]

Marketing Related [Member]

Marketing Related [Member]

Marketing Related [Member]

Product Rights [Member]

Product Rights [Member]

Innospec Fuel Specialties LLC [Member]

Innospec Fuel Specialties LLC [Member]

Innospec Widnes Limited [Member]

Innospec Widnes Limited [Member]

Bachman [Member]

Bachman [Member]

Bachman [Member]

Bachman [Member]

Bachman [Member]

Bachman [Member]

Bachman [Member]

Strata [Member]

Strata [Member]

Finetex [Member]

Finetex [Member]

Chemsil [Member]

Chemsil [Member]

Chemsil [Member]

Selling, General and Administrative Expenses [Member]

Selling, General and Administrative Expenses [Member]

Selling, General and Administrative Expenses [Member]

Selling, General and Administrative Expenses [Member]

Technology [Member]

Technology [Member]

Brand Names [Member]

Brand Names [Member]

Brand Names [Member]

Technology [Member]

Technology [Member]

Customer Relationships [Member]

Customer Relationships [Member]

Technology [Member]

Customer Relationships [Member]

Patents [Member]

Product Rights [Member]

Product Rights [Member]

Product Rights [Member]

Finite-Lived Intangible Assets [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Allocation of purchase price to other intangible assets

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$2.90

'

$8.50

'

$14.50

'

'

'

'

'

'

$34

Assets being amortized duration

'10 years

'

'

'

'

'

'

'

'

'13 years

'10 years

'

'5 years

'

'

'

'2 years

'

'

'

'

'

'

'

'

'

'

'10 years

'

'10 years

'5 years

'

'

'15 years

'

'14 years 6 months

'

'16 years 6 months

'11 years 6 months

'

'

'9 years

'

'

Amortization expense

11.1

4.1

4.4

'

'

1.9

0.7

4.1

1.5

'

0.3

0.3

'

'

1

0

'

'

0.7

0

1.7

1.6

'

'

'

'

'

'

'

'

0.1

0

'

'

'

'

'

'

'

'

'

1.3

0

'

Date of acquisition

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

8-Jul-04

'

'

4-Nov-13

'

'

4-Nov-13

'

4-Nov-13

'

24-Dec-12

4-Nov-13

'

'

30-Aug-13

'

'

Residual value

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

0

'

'

0

'

0

'

'

'

'

'

0

'

'

Intangible assets, recognized

'

'

'

'

'

'

'

'

'

4.2

'

'

'

'

'

'

1.5

'

'

'

'

'

'

'

'

'

9

2.3

2.8

4.8

'

'

'

'

'

'

'

18.3

28.2

7.1

'

'

'

'

Percent of remaining interest of entity acquired

'

'

'

'

'

50.00%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Intangible asset

175.5

106.2

'

2.9

0

33.9

25.4

58.7

44.2

'

2.9

2.9

19.5

10.1

'

'

1.5

1.5

'

'

22.1

22.1

'

28.4

34

0

'

'

'

'

'

'

'

'

'

'

'

'

'

'

2.9

'

'

'

Contract provisions offset against intangible assets

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

6.3

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Cost of goods, amortization

$3.80

$2.60

$2.90

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Other_Intangible_Assets_Schedu

Other Intangible Assets - Schedule of Future Amortization Estimated Expense (Detail) (Intangible Assets, Amortization Period [Member], USD $)	Dec. 31, 2013
In Millions, unless otherwise specified
Intangible Assets, Amortization Period [Member]	'
Finite-Lived Intangible Assets [Line Items]	'
2014	$16.60
2015	16.6
2016	16.6
2017	16.6
2018	$14.30

Deferred_Finance_Costs_Additio

Deferred Finance Costs - Additional Information (Detail) (USD $)	3 Months Ended	12 Months Ended					12 Months Ended			1 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013	Dec. 31, 2013	Dec. 31, 2013	Aug. 28, 2013	Dec. 31, 2011	Aug. 28, 2013
					Original Revolving Credit Facility [Member]	Amended Credit Facility [Member]	Revolving Credit Facility [Member]	Revolving Credit Facility [Member]	Revolving Credit Facility [Member]	Revolving Credit Facility [Member]
										Amended Credit Facility [Member]
Deferred Costs Capitalized Prepaid And Other Assets Disclosure [Line Items]	'	'	'	'	'	'	'	'	'	'
Term of revolving credit facility	'	'	'	'	'	'	'5 years	'	'	'5 years
Finance cost capitalized	$0.90	$0.90	'	'	'	'	'	'	'	'
Credit facility maximum borrowing capacity	'	'	'	'	100	150	'	100	100	150
Additional borrowing capacity	30	50	'	'	'	'	'	'	'	'
Credit Facility Term Ends	'	'2016-12	'	'	'	'	'	'	'	'
Amortization of deferred finance costs	'	$0.40	$0.40	$0.50	'	'	'	'	'	'

Deferred_Finance_Costs_Summary

Deferred Finance Costs - Summary of Deferred Financing Cost (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Deferred Costs Capitalized Prepaid And Other Assets Disclosure [Abstract]	'	'
Gross cost	$2.60	$1.70
Accumulated amortization	-0.8	-0.4
Deferred Finance Costs, Net	$1.80	$1.30

Pension_Plans_Additional_Infor

Pension Plans - Additional Information (Detail) (USD $)

3 Months Ended

12 Months Ended

12 Months Ended

12 Months Ended

In Millions, unless otherwise specified

Jun. 30, 2010

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2010

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Dec. 31, 2013

United Kingdom Government Gilts [Member]

United Kingdom Government Gilts [Member]

Debt Securities [Member]

Equity Securities [Member]

United Kingdom Plan [Member]

United Kingdom Plan [Member]

United Kingdom Plan [Member]

United Kingdom Plan [Member]

United Kingdom Plan [Member]

United Kingdom Plan [Member]

United Kingdom Plan [Member]

United Kingdom Plan [Member]

United Kingdom Plan [Member]

United Kingdom Plan [Member]

United Kingdom Plan [Member]

German Plan [Member]

Index-Tracking Funds [Member]

Index-Tracking Funds [Member]

Debt Securities [Member]

Debt Securities [Member]

Debt Securities [Member]

Equity Securities [Member]

Equity Securities [Member]

Equity Securities [Member]

Defined Benefit Plan Disclosure [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Retirement age of service

'

'65 years

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Reduced in Projected Benefit Obligation (PBO)

$17.10

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Remaining life expectancy of Plan pensioners

'

'

'

'15 years

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Average remaining life expectancy of the inactive participants

'

'24 years

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Annual cash contribution

'

11

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Percentage change in discount rate

'

0.25%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Amount change in PBO due to discount rate

'

28

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Amount change in net pension charge due to discount rate

'

0.5

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Amount change in PBO due to change price inflation

'

22

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Amount change in net pension charge due to change price inflation

'

1.7

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Percentage change in price inflation

'

0.25%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Percentage of asset allocation, actual

'

'

'

'

25.00%

25.00%

'

'

'

'

'

55.00%

55.00%

'

'

'

'

'

'

'

Asset allocation

'

'

'

'

'

'

65.00%

35.00%

100.00%

100.00%

100.00%

'

'

61.00%

61.00%

66.00%

35.00%

33.00%

29.00%

'

Maximum percentage of Plan's assets invested in individual company's investment funds

'

5.00%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Accumulated benefit obligation for the Plan

'

819.8

805.3

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Amount of unrecognized actuarial net losses

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

1.6

Amount of unrecognized actuarial net losses, net of tax

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

0.6

Amount of contributions to defined contribution schemes

'

$7.70

$7.40

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Pension_Plans_Defined_Benefit_

Pension Plans - Defined Benefit Pension Plan (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Equity Securities [Member]	'	'	'
Plan asset allocation by category (%):	'	'	'
Total plan asset allocation by category	35.00%	'	'
Debt Securities [Member]	'	'	'
Plan asset allocation by category (%):	'	'	'
Total plan asset allocation by category	65.00%	'	'
United Kingdom Plan [Member]	'	'	'
Plan net pension charge/(credit):	'	'	'
Service cost	$1.60	$1.60	$1.60
Interest cost on PBO	31.3	32.2	36.6
Expected return on plan assets	-35.5	-34.1	-36.7
Amortization of prior service credit	-1.3	-1.3	-1.3
Amortization of actuarial net losses	6.2	3.2	2.7
Net pension charge	$2.30	$1.60	$2.90
Plan assumptions at December 31, (%):	'	'	'
Discount rate	4.40%	4.15%	4.75%
Inflation rate	2.55%	2.20%	2.15%
Rate of return on plan assets	4.85%	4.90%	4.85%
Plan asset allocation by category (%):	'	'	'
Total plan asset allocation by category	100.00%	100.00%	100.00%
United Kingdom Plan [Member] | Equity Securities [Member]	'	'	'
Plan assumptions at December 31, (%):	'	'	'
Rate of return on plan assets	7.50%	7.25%	7.70%
Plan asset allocation by category (%):	'	'	'
Total plan asset allocation by category	35.00%	33.00%	29.00%
United Kingdom Plan [Member] | Debt Securities [Member]	'	'	'
Plan assumptions at December 31, (%):	'	'	'
Rate of return on plan assets	3.40%	3.65%	3.60%
Plan asset allocation by category (%):	'	'	'
Total plan asset allocation by category	61.00%	61.00%	66.00%
United Kingdom Plan [Member] | Cash [Member]	'	'	'
Plan asset allocation by category (%):	'	'	'
Total plan asset allocation by category	4.00%	6.00%	5.00%

Pension_Plans_Movement_in_PBO_

Pension Plans - Movement in PBO and Fair Value of Plan Assets (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Change in PBO:	'	'	'
Actuarial losses/(gains)	($6.70)	($58.50)	$19.50
United Kingdom Plan [Member]	'	'	'
Change in PBO:	'	'	'
Service cost	1.6	1.6	1.6
Interest cost	31.3	32.2	36.6
Amortization of prior service cost/(credit)	1.3	1.3	1.3
Benefits paid	-39.4	-43.9	'
Fair value of plan assets:	'	'	'
Opening balance	768.6	708.8	'
Benefits paid	-39.4	-43.9	'
Actual contributions by employer	10.8	9.2	'
Actual return on assets	35.5	61.2	'
Exchange effect	14.8	33.3	'
Closing balance	790.3	768.6	708.8
United Kingdom Plan [Member] | Pension Benefit Obligation [Member]	'	'	'
Change in PBO:	'	'	'
Opening balance	805.3	687.4	'
Service cost	1.6	1.6	'
Interest cost	31.3	32.2	'
Benefits paid	-39.4	-43.9	'
Actuarial losses/(gains)	5.9	94.4	'
Exchange effect	15.1	33.6	'
Closing balance	819.8	805.3	'
Fair value of plan assets:	'	'	'
Benefits paid	-39.4	-43.9	'
German Plan [Member]	'	'	'
Change in PBO:	'	'	'
Opening balance	9.3	6.3	'
Service cost	0.2	0.1	0.2
Interest cost	0.3	0.3	0.3
Amortization of prior service cost/(credit)	-0.1	0	0
Benefits paid	-0.2	-0.2	'
Actuarial losses/(gains)	-0.4	2.6	'
Exchange effect	0.5	0.2	'
Closing balance	9.6	9.3	6.3
Fair value of plan assets:	'	'	'
Benefits paid	($0.20)	($0.20)	'

Pension_Plans_Fair_Value_of_Pe

Pension Plans - Fair Value of Pension Assets (Detail) (United Kingdom Plan [Member], USD $)	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
In Millions, unless otherwise specified
Fair value of pension assets	'	'	'
Total assets at fair value	$761.20	$718.80	'
Cash	29.1	49.8	'
Total plan assets	790.3	768.6	708.8
Debt Securities issued by U.S. Government and Government Agencies [Member]	'	'	'
Fair value of pension assets	'	'	'
Total assets at fair value	1.3	1.6	'
Debt Securities Issued by Non-U.S. Government and Government Agencies [Member]	'	'	'
Fair value of pension assets	'	'	'
Total assets at fair value	198.7	191.3	'
Equity Securities Held for Proprietary Investment Purposes [Member]	'	'	'
Fair value of pension assets	'	'	'
Total assets at fair value	156.7	134.8	'
Corporate Debt Securities [Member]	'	'	'
Fair value of pension assets	'	'	'
Total assets at fair value	275.5	284.6	'
Residential Mortgage-Backed Securities [Member]	'	'	'
Fair value of pension assets	'	'	'
Total assets at fair value	0.2	0.2	'
Other Asset-Backed Securities [Member]	'	'	'
Fair value of pension assets	'	'	'
Total assets at fair value	3.8	3.1	'
Real Estate [Member]	'	'	'
Fair value of pension assets	'	'	'
Total assets at fair value	61.4	33.2	'
Other Assets [Member]	'	'	'
Fair value of pension assets	'	'	'
Total assets at fair value	63.6	70	'
Derivatives (Level 1 Measurement) [Member]	'	'	'
Fair value of pension assets	'	'	'
Total assets at fair value	697.6	648.8	'
Cash	29.1	49.8	'
Total plan assets	726.7	698.6	'
Derivatives (Level 1 Measurement) [Member] | Debt Securities issued by U.S. Government and Government Agencies [Member]	'	'	'
Fair value of pension assets	'	'	'
Total assets at fair value	1.3	1.6	'
Derivatives (Level 1 Measurement) [Member] | Debt Securities Issued by Non-U.S. Government and Government Agencies [Member]	'	'	'
Fair value of pension assets	'	'	'
Total assets at fair value	198.7	191.3	'
Derivatives (Level 1 Measurement) [Member] | Equity Securities Held for Proprietary Investment Purposes [Member]	'	'	'
Fair value of pension assets	'	'	'
Total assets at fair value	156.7	134.8	'
Derivatives (Level 1 Measurement) [Member] | Corporate Debt Securities [Member]	'	'	'
Fair value of pension assets	'	'	'
Total assets at fair value	275.5	284.6	'
Derivatives (Level 1 Measurement) [Member] | Residential Mortgage-Backed Securities [Member]	'	'	'
Fair value of pension assets	'	'	'
Total assets at fair value	0.2	0.2	'
Derivatives (Level 1 Measurement) [Member] | Other Asset-Backed Securities [Member]	'	'	'
Fair value of pension assets	'	'	'
Total assets at fair value	3.8	3.1	'
Derivatives (Level 1 Measurement) [Member] | Real Estate [Member]	'	'	'
Fair value of pension assets	'	'	'
Total assets at fair value	61.4	33.2	'
Significant Other Observable Inputs (Level 2) [Member]	'	'	'
Fair value of pension assets	'	'	'
Total assets at fair value	25.3	39	'
Total plan assets	25.3	39	'
Significant Other Observable Inputs (Level 2) [Member] | Other Assets [Member]	'	'	'
Fair value of pension assets	'	'	'
Total assets at fair value	25.3	39	'
Non-financial Assets and Liabilities (Level 3 Measurement) [Member]	'	'	'
Fair value of pension assets	'	'	'
Total assets at fair value	38.3	31	'
Total plan assets	38.3	31	'
Non-financial Assets and Liabilities (Level 3 Measurement) [Member] | Other Assets [Member]	'	'	'
Fair value of pension assets	'	'	'
Total assets at fair value	$38.30	$31	'

Pension_Plans_Reconciliation_o

Pension Plans - Reconciliation of Fair Value of Plan Assets (Detail) (United Kingdom Plan [Member], Non-financial Assets and Liabilities (Level 3 Measurement) [Member], Other Assets [Member], USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
United Kingdom Plan [Member] | Non-financial Assets and Liabilities (Level 3 Measurement) [Member] | Other Assets [Member]	'	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]	'	'
Beginning balance	$31	$28.10
Realized/unrealized gains/(losses):	'	'
Relating to assets still held at the reporting date	3.5	1.3
Relating to assets sold during the period	0	0
Purchases, issuances and settlements	3.6	0.5
Exchange effect	0.2	1.1
Ending balance	$38.30	$31

Pension_Plans_Plan_Net_Pension

Pension Plans - Plan Net Pension Charge (Detail) (United Kingdom Plan [Member], USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Defined Benefit Plan Disclosure [Line Items]	'	'	'
Service cost	$1.60	$1.60	$1.60
Interest cost on PBO	31.3	32.2	36.6
Expected return on plan assets	-35.5	-34.1	-36.7
Amortization of prior service credit	-1.3	-1.3	-1.3
Net pension charge	2.3	1.6	2.9
Forecast [Member]	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'
Service cost	1.7	'	'
Interest cost on PBO	34.7	'	'
Expected return on plan assets	-37.3	'	'
Amortization of prior service credit	-1.3	'	'
Amortization of actuarial net losses	5.5	'	'
Net pension charge	$3.30	'	'

Pension_Plans_Expected_Benefit

Pension Plans - Expected Benefit Payments (Detail) (USD $)	Dec. 31, 2013
In Millions, unless otherwise specified
Defined Benefit Plan Estimated Future Benefit Payments [Abstract]	'
2014	$49.70
2015	47
2016	47.9
2017	48.5
2018	49.2
2019 - 2023	$258

Pension_Plans_Unfunded_Defined

Pension Plans - Unfunded Defined Benefit Pension Plan (Detail) (German Plan [Member], USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
German Plan [Member]	'	'	'
German plan net pension charge:	'	'	'
Service cost	$0.20	$0.10	$0.20
Interest cost on PBO	0.3	0.3	0.3
Amortization of prior service cost	-0.1	0	0
Amortization of actuarial net loss/(gain)	0.2	0	0
Net pension charge	$0.60	$0.40	$0.50
German plan assumptions (%):	'	'	'
Discount rate	3.50%	3.25%	5.00%
Inflation rate	2.00%	2.00%	2.00%
Rate of increase in compensation levels	2.75%	2.75%	2.75%

Income_Taxes_RollForward_of_Un

Income Taxes - Roll-Forward of Unrecognized Tax Benefits and Associated Accrued Interest and Penalties (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Tax Contingency [Line Items]	'	'	'
Opening balance at January 1	$12.80	$12.60	$8.60
Additions related to tax positions taken in the current period	'	0.2	5.2
Additions for tax positions of prior periods	0.8	0.2	0.7
Reductions due to lapsed statutes of limitations	-0.6	-0.2	'
Reductions for tax positions of prior periods	'	'	-1.9
Closing balance at December 31	13	12.8	12.6
Current	-6.8	-3	-3.2
Non-current	6.2	9.8	9.4
Interest and Penalties [Member]	'	'	'
Income Tax Contingency [Line Items]	'	'	'
Opening balance at January 1	0.6	0.4	0.3
Additions related to tax positions taken in the current period	'	0	0
Additions for tax positions of prior periods	0.6	0.2	0.2
Reductions due to lapsed statutes of limitations	-0.1	0	'
Reductions for tax positions of prior periods	'	'	-0.1
Closing balance at December 31	1.1	0.6	0.4
Current	-0.6	-0.3	-0.3
Non-current	0.5	0.3	0.1
Unrecognized Tax Benefits [Member]	'	'	'
Income Tax Contingency [Line Items]	'	'	'
Opening balance at January 1	12.2	12.2	8.3
Additions related to tax positions taken in the current period	'	0.2	5.2
Additions for tax positions of prior periods	0.2	0	0.5
Reductions due to lapsed statutes of limitations	-0.5	-0.2	'
Reductions for tax positions of prior periods	'	'	-1.8
Closing balance at December 31	11.9	12.2	12.2
Current	-6.2	-2.7	-2.9
Non-current	$5.70	$9.50	$9.30

Income_Taxes_Additional_Inform

Income Taxes - Additional Information (Detail) (USD $)	3 Months Ended		12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Mar. 31, 2013	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Income Tax Contingency [Line Items]	'	'	'	'	'	'
Unrecognized tax benefits, interest and penalties	$13	'	$13	'	'	'
Unrecognized tax benefits	0.2	'	'	'	'	'
Reduction in unrecognized tax benefits	'	0.5	'	'	'	'
Cash payments for income taxes	'	'	21.1	13.1	18.1	'
Operating loss carry forwards	0.3	'	0.3	0.3	'	'
Operating loss carry forwards valuation allowance	0	'	0	'	'	'
Foreign tax credit carry forwards	0	'	0	0	7.5	10.8
Unremitted earnings	'	'	605	717	'	'
Foreign Income [Member]	'	'	'	'	'	'
Income Tax Contingency [Line Items]	'	'	'	'	'	'
Foreign tax credit carry forwards	$4.50	'	$4.50	$5.50	'	'

Income_Taxes_Sources_of_Income

Income Taxes - Sources of Income Before Income Taxes (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Tax Disclosure [Abstract]	'	'	'
Domestic	$10	$5.60	($42.60)
Foreign	82.8	87.7	92.8
Income before income taxes	$92.80	$93.30	$50.20

Income_Taxes_Components_of_Inc

Income Taxes - Components of Income Tax Charges (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Current:	'	'	'
Federal	$1.60	$2.90	$5.40
Foreign	6.8	11.8	13.6
Total current income tax	8.4	14.7	19
Deferred:	'	'	'
Federal	1.8	12.3	-12.8
Foreign	4.8	-0.6	-3.1
Total Deferred Income Tax	6.6	11.7	-15.9
Total	$15	$26.40	$3.10

Income_Taxes_Factors_Effecting

Income Taxes - Factors Effecting Effective Tax Rate from U.S. Federal Statutory Rate (Detail)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Schedule Of Effective Income Tax Rate Reconciliation [Line Items]	'	'	'
Statutory rate	35.00%	35.00%	35.00%
Foreign income inclusions	6.10%	48.90%	20.50%
Impairment of Octane Additives segment goodwill	0.50%	0.50%	1.30%
Foreign tax credits	-1.90%	-38.30%	-25.80%
Pension (credit)/charge	-0.30%	-0.30%	-9.70%
Foreign tax rate differential	-14.60%	-16.40%	-19.10%
Permanent tax adjustments	-2.50%	-0.20%	0.30%
Amortization	1.10%	0.50%	0.70%
Tax (credit)/charge from previous years	-2.90%	-0.60%	-1.90%
Net charge/(credit) from unrecognized tax benefits	0.20%	0.30%	7.70%
Other items and adjustments, net	-5.40%	-0.50%	2.00%
Effective Income Tax Rate	16.20%	28.30%	6.20%
United Kingdom [Member]	'	'	'
Schedule Of Effective Income Tax Rate Reconciliation [Line Items]	'	'	'
Foreign tax rate differential	0.90%	-0.60%	-4.80%

Income_Taxes_Details_of_Deferr

Income Taxes - Details of Deferred Tax Assets and Liabilities (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
In Millions, unless otherwise specified
Deferred tax assets:	'	'	'	'
Foreign tax credits	$4.50	$5.50	'	'
Accrued expenses	3.4	4.6	'	'
Stock options	5.2	5.5	'	'
Excess of tax over book basis in property, plant and equipment	0.9	1.1	'	'
Net operating loss carry forwards	0.3	0.3	'	'
Pension liabilities	6.5	9.2	'	'
Other intangible assets	1	0	'	'
Other	3.9	4.7	'	'
Valuation allowance	0	0	-7.5	-10.8
Deferred tax liabilities:	'	'	'	'
Goodwill amortization	-7.2	-6.9	'	'
Other intangible assets	-0.3	-0.9	'	'
Excess of book over tax basis in tax deductible goodwill	-0.2	0	'	'
Excess of book over tax basis in intangible assets	-7.5	0	'	'
Other	-2.9	-3.2	'	'
Total net deferred tax asset	7.6	19.9	'	'
Deferred taxes are included within the consolidated balance sheets as follows:	'	'	'	'
Deferred tax assets	17.3	23.7	'	'
Deferred tax liabilities	-9.7	-3.8	'	'
Total net deferred tax asset	7.6	19.9	'	'
Current portion of deferred tax assets	8.7	11	'	'
Deferred tax assets, net of current portion	8.6	12.7	'	'
Current portion of deferred tax liabilities	-0.2	-0.2	'	'
Deferred tax liabilities, net of current portion	-9.5	-3.6	'	'
Total net deferred tax asset	$7.60	$19.90	'	'

Income_Taxes_Details_of_Deferr1

Income Taxes - Details of Deferred Tax Asset Valuation Allowance (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Tax Disclosure [Abstract]	'	'	'
At January 1	$0	($7.50)	($10.80)
Change in foreign tax credits	0	7.5	3.3
At December 31	$0	$0	($7.50)

LongTerm_Debt_Schedule_of_Long

Long-Term Debt - Schedule of Long-Term Debt (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Debt Instrument [Line Items]	'	'
Long-term debt	$148	$30
Less current portion	-5.3	-5
Long-term debt, net of current portion	142.7	25
Revolving Credit Facility [Member]	'	'
Debt Instrument [Line Items]	'	'
Long-term debt	142	20
Promissory Note [Member]	'	'
Debt Instrument [Line Items]	'	'
Long-term debt	5	10
Other Long-Term Debt [Member]	'	'
Debt Instrument [Line Items]	'	'
Long-term debt	$1	$0

LongTerm_Debt_Additional_Infor

Long-Term Debt - Additional Information (Detail) (USD $)

3 Months Ended

12 Months Ended

12 Months Ended

1 Months Ended

12 Months Ended

1 Months Ended

In Millions, unless otherwise specified

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Dec. 31, 2013

Dec. 31, 2011

Aug. 28, 2013

Dec. 31, 2011

Dec. 31, 2011

Aug. 28, 2013

Dec. 31, 2013

Dec. 31, 2011

Dec. 31, 2013

Aug. 28, 2013

Revolving Credit Facility [Member]

Revolving Credit Facility [Member]

Revolving Credit Facility [Member]

Revolving Credit Facility [Member]

Revolving Credit Facility [Member]

Additional Amount to be Committed by Lenders [Member]

Promissory Note [Member]

Promissory Note [Member]

Amended Credit Facility [Member]

Amended Credit Facility [Member]

Minimum [Member]

Maximum [Member]

NewMarket Corporation [Member]

NewMarket Corporation [Member]

Revolving Credit Facility [Member]

Installment

Schedule Of Debt Instruments [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Revolving credit facility term

'

'

'

'

'5 years

'

'

'

'

'

'

'

'

'5 years

Borrowing amount through revolving credit facility

'

'

'

'

'

$100

$100

'

'

'

'

'

$150

$150

Margin rate based on U.S. dollar LIBOR

'

'

'

'

'

'

'

1.50%

2.25%

'

'

'

'

'

Expiration date of facility

'

'

'

'

31-Dec-16

14-Dec-16

'

'

'

'

'

'

'

'

Revolving credit facility, drawn down amount

30

145

18

51

'

'

'

'

'

50

'

'

'

'

Maximum ratio of net debt to EBITDA

'

2.5

'

'

'

'

'

'

'

'

'

'

'

'

Minimum ratio of EBITDA to net interest

'

4

'

'

'

'

'

'

'

'

'

'

'

'

Promissory note issued

'

'

'

'

'

'

'

'

'

'

'

15

'

'

Carrying simple interest per annum

'

'

'

'

'

'

'

'

'

'

1.00%

1.00%

'

'

Number of repayment installment

'

'

'

'

'

'

'

'

'

'

3

'

'

'

Weighted average rate of interest on borrowings

1.60%

1.60%

1.60%

'

'

'

'

'

'

'

'

'

'

'

Payments of interest on long-term debt

'

1

0.5

1.8

'

'

'

'

'

'

'

'

'

'

Net cash outflows in respect of refinancing costs

'

$0.90

$0

$1.70

'

'

'

'

'

'

'

'

'

'

Plant_Closure_Provisions_Addit

Plant Closure Provisions - Additional Information (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Restructuring Cost and Reserve [Line Items]	'	'	'
Remediation charge for changes in the scope and cost of future remediation activities	$0.20	$0.20	$0.60
Expenditure	2	2.7	3.8
Severance [Member]	'	'	'
Restructuring Cost and Reserve [Line Items]	'	'	'
Number of reporting segment	3	'	'
Expenditure	0.1	0.6	0.7
Remediation [Member]	'	'	'
Restructuring Cost and Reserve [Line Items]	'	'	'
Accretion expense recognized	2.6	'	'
Remediation charge for changes in the scope and cost of future remediation activities	1.3	'	'
Discount rate of remediation provision	8.92%	'	'
Expenditure	$1.90	$2.10	$3.10

Plant_Closure_Provisions_Movem

Plant Closure Provisions - Movements in Plant Closure and Restructuring Provisions (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Restructuring Cost and Reserve [Line Items]	'	'	'
Beginning Balance	$30.40	$28.60	$27.50
Charge for the period	3.9	4.2	5.1
Utilized in the period	-2	-2.7	-3.8
Exchange effect	0.1	0.3	-0.2
Ending Balance	32.4	30.4	28.6
Due within one year	-6.2	-5.1	-4.1
Due after one year	26.2	25.3	24.5
Severance [Member]	'	'	'
Restructuring Cost and Reserve [Line Items]	'	'	'
Beginning Balance	1.1	1.5	1.5
Charge for the period	0	0.2	0.7
Utilized in the period	-0.1	-0.6	-0.7
Exchange effect	0	0	0
Ending Balance	1	1.1	1.5
Due within one year	0	-0.1	-0.5
Due after one year	1	1	1
Other Restructuring [Member]	'	'	'
Restructuring Cost and Reserve [Line Items]	'	'	'
Beginning Balance	0	0	0.1
Charge for the period	0	0	-0.1
Utilized in the period	0	0	0
Exchange effect	0	0	0
Ending Balance	0	0	0
Due within one year	0	0	0
Due after one year	0	0	0
Remediation [Member]	'	'	'
Restructuring Cost and Reserve [Line Items]	'	'	'
Beginning Balance	29.3	27.1	25.9
Charge for the period	3.9	4	4.5
Utilized in the period	-1.9	-2.1	-3.1
Exchange effect	0.1	0.3	-0.2
Ending Balance	31.4	29.3	27.1
Due within one year	-6.2	-5	-3.6
Due after one year	$25.20	$24.30	$23.50

Deferred_Income_Summary_of_Def

Deferred Income - Summary of Deferred Income (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Deferred Revenue Disclosure [Abstract]	'	'
Deferred income	$1.50	$2.30
Less current portion	-0.3	-1.4
Non-current deferred income	$1.20	$0.90

Deferred_Income_Additional_Inf

Deferred Income - Additional Information (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Deferred Revenue Disclosure [Abstract]	'	'
Non-current deferred income	$1.20	$0.90

Profit_on_Disposal_Net_Summary

Profit on Disposal, Net - Summary of Profit on Disposal, Net (Detail) (USD $)	3 Months Ended	12 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Gain Loss On Disposition [Line Items]	'	'	'	'
Profit on disposal, net	'	$0	$0.10	$0
United Kingdom Real Estate [Member]	'	'	'	'
Gain Loss On Disposition [Line Items]	'	'	'	'
Profit on disposal, net	0.1	0	0.1	0
US Real Estate [Member]	'	'	'	'
Gain Loss On Disposition [Line Items]	'	'	'	'
Profit on disposal, net	'	$0	$0	$0

Profit_on_Disposal_Net_Additio

Profit on Disposal, Net - Additional Information (Detail) (USD $)	3 Months Ended	12 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Property, Plant and Equipment [Line Items]	'	'	'	'
Profit on disposal, net	'	$0	$0.10	$0
United Kingdom Real Estate [Member]	'	'	'	'
Property, Plant and Equipment [Line Items]	'	'	'	'
Profit on disposal, net	$0.10	$0	$0.10	$0

Fair_Value_Measurements_Carryi

Fair Value Measurements - Carrying Amount and Fair Values of the Company's Assets and Liabilities Measured on a Recurring Basis (Detail) (Recurring [Member], USD $)	Dec. 31, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Carrying Amount [Member]	'	'
Non-derivatives:	'	'
Cash and cash equivalents	$80.20	$22.40
Short-term investments	6.6	5.1
Non-derivatives:	'	'
Long-term debt (including current portion)	148	30
Carrying Amount [Member] | Non-financial Assets and Liabilities (Level 3 Measurement) [Member]	'	'
Non-financial liabilities (Level 3 measurement):	'	'
Acquisition-related contingent consideration	4.6	4.3
Carrying Amount [Member] | Non-financial Assets and Liabilities (Level 3 Measurement) [Member] | Octane Additives [Member]	'	'
Non-financial assets (Level 3 measurement):	'	'
Goodwill - Octane Additives	0	1.3
Carrying Amount [Member] | Non-financial Assets and Liabilities (Level 3 Measurement) [Member] | Stock Equivalent Units [Member]	'	'
Non-financial liabilities (Level 3 measurement):	'	'
Stock equivalent units	12.1	12.6
Carrying Amount [Member] | Derivatives (Level 1 Measurement) [Member]	'	'
Derivatives (Level 1 measurement):	'	'
Other non-current assets: Commodity swaps	0	0.1
Foreign currency forward exchange contracts	1	0.8
Fair Value [Member]	'	'
Non-derivatives:	'	'
Cash and cash equivalents	80.2	22.4
Short-term investments	6.6	5.1
Non-derivatives:	'	'
Long-term debt (including current portion)	148	30
Fair Value [Member] | Non-financial Assets and Liabilities (Level 3 Measurement) [Member]	'	'
Non-financial liabilities (Level 3 measurement):	'	'
Acquisition-related contingent consideration	4.6	4.3
Fair Value [Member] | Non-financial Assets and Liabilities (Level 3 Measurement) [Member] | Octane Additives [Member]	'	'
Non-financial assets (Level 3 measurement):	'	'
Goodwill - Octane Additives	0	1.3
Fair Value [Member] | Non-financial Assets and Liabilities (Level 3 Measurement) [Member] | Stock Equivalent Units [Member]	'	'
Non-financial liabilities (Level 3 measurement):	'	'
Stock equivalent units	12.1	12.6
Fair Value [Member] | Derivatives (Level 1 Measurement) [Member]	'	'
Derivatives (Level 1 measurement):	'	'
Other non-current assets: Commodity swaps	0	0.1
Foreign currency forward exchange contracts	$1	$0.80

Fair_Value_Measurements_Summar

Fair Value Measurements - Summary of Cumulative Gains and Losses on the Interest Rate Swaps and Commodity Swaps (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Fair Value Disclosures [Abstract]	'	'
Beginning Balance	$0.10	$0.10
Change in fair value	-0.1	0
Ending Balance	$0	$0.10

Fair_Value_Measurements_Additi

Fair Value Measurements - Additional Information (Detail) (USD $)	3 Months Ended	12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
		Commodity Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Expected unrealized gain to be reclassified into earnings	$0.10	'
Unrealized gain on commodity hedges	'	$0.20

Derivative_Instruments_and_Ris2

Derivative Instruments and Risk Management - Additional Information (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Derivative Instruments And Hedging Activities Disclosure [Abstract]	'	'
Derivative expiration date	6-Feb-12	'
Loss recognized in earnings	$0.10	$0.10
Maturity period of foreign currency forward exchange contracts	'4 years	'

Derivative_Instruments_and_Ris3

Derivative Instruments and Risk Management - Summary of Commodity Swaps (Detail) (Derivatives (Level 1 Measurement) [Member], Recurring [Member], USD $)	Dec. 31, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Carrying Amount [Member]	'	'
Derivative [Line Items]	'	'
Commodity swaps	$0	$0.10
Fair Value [Member]	'	'
Derivative [Line Items]	'	'
Commodity swaps	$0	$0.10

Derivative_Instruments_and_Ris4

Derivative Instruments and Risk Management - Summary of Commodity Swaps (Parenthetical) (Detail)	Dec. 31, 2013	Dec. 31, 2012
	T	T
Derivative Instruments And Hedging Activities Disclosure [Abstract]	'	'
Commodity swaps, notional quantity	0	275

Derivative_Instruments_and_Ris5

Derivative Instruments and Risk Management - Summary of Foreign Currency Forward Exchange Contracts Which Have Not Been Designated as Hedging Instruments, and Their Impact on Income Statement (Detail) (Not Designated as Hedging Instrument [Member], Foreign Currency Forward Exchange Contracts [Member], Other Income/(Expense) [Member], USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Not Designated as Hedging Instrument [Member] | Foreign Currency Forward Exchange Contracts [Member] | Other Income/(Expense) [Member]	'	'	'
Summary of foreign currency forward exchange contracts which have not been designated as hedging instruments, and their impact on the income statement	'	'	'
Amount of Gain/(Loss) Recognized in Income	($1.50)	$1.20	$1.30

Commitments_and_Contingencies_1

Commitments and Contingencies - Additional Information (Detail) (USD $)	0 Months Ended	1 Months Ended	3 Months Ended	12 Months Ended
In Millions, except Share data, unless otherwise specified	Sep. 19, 2012	Sep. 30, 2011	Mar. 31, 2010	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Commitment And Contingencies [Line Items]	'	'	'	'	'	'
Operating leases, rent expense	'	'	'	$3.10	$2.90	$2.60
Settlement to resolve investigation matter	'	'	40.2	'	'	'
Litigation Settlement period for payment	'	'	'	'4 years	'	'
Stated claim inclusive of costs and expenses	42.3	'	'	'	'	'
Promissory note issued	'	'	'	15	'	'
Payment made in the form of stock	'	5	'	'	'	'
Stock issued for payment	'	195,313	'	0	0	0
Contingent liabilities	'	'	'	3.8	'	'
NewMarket Corporation [Member]	'	'	'	'	'	'
Commitment And Contingencies [Line Items]	'	'	'	'	'	'
Settlement to resolve investigation matter	'	'	'	45	'	'
Litigation settlement amount paid	'	$25	'	'	'	'
NewMarket Corporation [Member] | Promissory Note [Member]	'	'	'	'	'	'
Commitment And Contingencies [Line Items]	'	'	'	'	'	'
Carrying simple interest per annum	'	'	'	1.00%	'	1.00%
Number of repayment installment	'	'	'	3	'	'

Commitments_and_Contingencies_2

Commitments and Contingencies - Future Commitments under Non-Cancelable Operating Leases (Detail) (USD $)	Dec. 31, 2013
In Millions, unless otherwise specified
Operating Leases Future Minimum Payments Due [Abstract]	'
2014	$2.70
2015	2.6
2016	2.3
2017	1.9
2018	1.7
Thereafter	2.9
Total Commitments	$14.10

Commitments_and_Contingencies_3

Commitments and Contingencies - Schedule of Expected Settlement Payment (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013
Payment Of Commitment And Contingencies [Line Items]	'
Fines, penalties and disgorgements	$40.20
Fees and associated expenses	3.9
Less discounting to fair value	0
Government investigations and other matters Expenses, Total	44.1
Amounts paid	-43.8
Exchange effect	0
Expected total amounts paid	0.3
Due within one year	-0.3
Total long term amount	0
Government Authorities [Member]	'
Payment Of Commitment And Contingencies [Line Items]	'
Fines, penalties and disgorgements	40.2
Fees and associated expenses	0
Less discounting to fair value	0
Government investigations and other matters Expenses, Total	40.2
Amounts paid	-40.2
Exchange effect	0
Expected total amounts paid	0
Due within one year	0
Total long term amount	0
Compliance Monitor [Member]	'
Payment Of Commitment And Contingencies [Line Items]	'
Fines, penalties and disgorgements	0
Fees and associated expenses	3.9
Less discounting to fair value	0
Government investigations and other matters Expenses, Total	3.9
Amounts paid	-3.6
Exchange effect	0
Expected total amounts paid	0.3
Due within one year	-0.3
Total long term amount	$0

Stockholders_Equity_Stockholde

Stockholder's Equity - Stockholder's Equity (Detail)	1 Months Ended	12 Months Ended
	Sep. 30, 2011	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Equity [Abstract]	'	'	'	'
Common Stock, Beginning balance	'	29,554,500	29,554,500	29,554,500
Treasury Stock, Beginning balance	'	6,222	6,507	5,851
Exercise of options	'	0	0	0
Exercise of options, Treasury Stock	'	-632	-333	-236
Acquisition-related stock issued	'	0	0	0
Acquisition-related stock issued, Treasury Stock	'	-471	0	0
Stock purchases	'	0	0	0
Stock purchases, Treasury Stock	'	89	48	1,087
Settlement of NewMarket Corporation civil complaint	195,313	0	0	0
Settlement of NewMarket Corporation civil complaint, Treasury Stock	'	0	0	-195
Common stock, Ending balance	'	29,554,500	29,554,500	29,554,500
Ending balance, Treasury Stock	'	5,208	6,222	6,507

Stockholders_Equity_Additional

Stockholder's Equity - Additional Information (Detail)	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Equity [Abstract]	'	'	'	'
Common stock, shares authorized	40,000,000	40,000,000	'	'
Number of shares issued	29,554,500	29,554,500	29,554,500	29,554,500
Treasury stock, shares	5,207,947	6,222,076	'	'

StockBased_Compensation_Plans_1

Stock-Based Compensation Plans - Additional Information (Detail) (USD $)	12 Months Ended
In Millions, except Share data, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
	Stock_Plan
	Executives
	Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Accrued liabilities	$73.50	$72.10	'
Minimum out-performance of Innospec share price versus Russell 2000 Index for long-term incentive plan to be payable	10.00%	'	'
Long-term incentive plan term	'5 years	'	'
Maximum bonus under long-term incentive plan	8	'	'
Stock Options Plan [Member]	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Number of active stock option plans	5	'	'
Number of active stock option plans for employees	2	'	'
Number of active stock option plans for non-employee directors	1	'	'
Number of active stock option plans for key executives	1	'	'
Expiration term for stock granted	'10 years	'	'
Aggregate number of shares of common stock reserved for issuance which can be granted	2,640,000	'	'
Number exercisable and fully vested	186,741	'	'
Fully vested stock options with performance conditions attached	77,001	'	'
Total compensation cost of SEUs	2.5	3.1	3.1
Total intrinsic value of options exercised	4.7	1.5	2.2
Total compensation cost related to non-vested stock options not yet recognized	2.7	'	'
Expected compensation cost recognized over the weighted average period	'2 years 26 days	'	'
Cash tax benefit realized from stock option exercises	5.7	2.7	1.7
Excess tax benefit	3.8	2.2	1.1
Stock Options Plan [Member] | Minimum [Member]	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Range of stock vesting period	'24 months	'	'
Stock Options Plan [Member] | Maximum [Member]	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Range of stock vesting period	'6 years	'	'
Stock Equivalent Units [Member]	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Expiration term for stock granted	'10 years	'	'
Fully vested stock options with performance conditions attached	57,677	'	'
Total compensation cost of SEUs	7.1	6.8	5.9
Total intrinsic value of options exercised	2.2	1.3	0.4
Expected compensation cost recognized over the weighted average period	'9 months 18 days	'	'
Accrued liabilities	$12.10	'	'
Number of exercisable SEUs	64,019	'	'
Stock Equivalent Units [Member] | Minimum [Member]	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Range of stock vesting period	'11 months	'	'
Stock Equivalent Units [Member] | Maximum [Member]	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Range of stock vesting period	'4 years	'	'

StockBased_Compensation_Plans_2

Stock-Based Compensation Plans - Assumptions Used to Determine Grant Date Fair Value of Options (Detail) (Black-Scholes Model [Member])	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Black-Scholes Model [Member]	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Dividend yield	0.11%	0.00%	0.20%
Expected life	'5 years	'5 years	'5 years
Volatility	41.10%	60.10%	78.30%
Risk free interest rate	0.46%	0.43%	1.22%

StockBased_Compensation_Plans_3

Stock-Based Compensation Plans - Summary of Transactions of the Company's Stock Option Plans (Detail) (Stock Options Plan [Member], USD $)	12 Months Ended
	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Outstanding, Number of Options, Beginning balance	1,001,241
Exercised, Number of Options	-629,152
Forfeited, Number of Options	-25,688
Outstanding, Number of Options, Ending balance	447,390
Outstanding, Weighted Average Exercise Price, Beginning balance	$6.27
Exercised, Weighted Average Exercise Price	$5.96
Forfeited, Weighted Average Exercise Price	$6.21
Outstanding, Weighted Average Exercise Price, Ending balance	$7.33
Discount [Member]	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Granted, Number of Options	78,828
Granted, Weighted Average Exercise Price	$0
Granted, Weighted Average Grant-Date Fair Value	$36.30
Market Value [Member]	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Granted, Number of Options	22,161
Granted, Weighted Average Exercise Price	$41.27
Granted, Weighted Average Grant-Date Fair Value	$16.09

StockBased_Compensation_Plans_4

Stock-Based Compensation Plans - Assumptions Used to Determine Fair Value of SEUs (Detail) (Stock Equivalent Units [Member])	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Stock Equivalent Units [Member]	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Dividend yield	1.08%	0.00%	0.00%
Volatility	37.61%	43.80%	64.20%
Risk free interest rate	0.78%	0.36%	0.36%

StockBased_Compensation_Plans_5

Stock-Based Compensation Plans - Summarizes the Transactions of the SEUs (Detail) (Stock Equivalent Units [Member], USD $)	12 Months Ended
	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Outstanding, Number of Options, Beginning balance	623,828
Exercised, Number of Options	-281,703
Forfeited, Number of Options	-4,861
Outstanding, Number of Options, Ending balance	403,262
Outstanding, Weighted Average Exercise Price, Beginning balance	$2.95
Exercised, Weighted Average Exercise Price	$2.25
Forfeited, Weighted Average Exercise Price	$5.04
Outstanding, Weighted Average Exercise Price, Ending balance	$3.64
Discount [Member]	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Granted, Number of Options	59,028
Granted, Weighted Average Exercise Price	$0
Granted, Weighted Average Grant-Date Fair Value	$35.29
Market Value [Member]	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Granted, Number of Options	6,970
Granted, Weighted Average Exercise Price	$41.31
Granted, Weighted Average Grant-Date Fair Value	$16.09

StockBased_Compensation_Plans_6

Stock-Based Compensation Plans - Fair Value of Liability Cash-Settled Stock Appreciation Rights (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]	'	'	'
Balance at January 1	$1.30	$2.20	$0.80
Compensation charge	0	5.8	1.4
Cash paid	-1.3	-6.7	0
Balance at December 31	$0	$1.30	$2.20

StockBased_Compensation_Plans_7

Stock-Based Compensation Plans - Assumptions Used in the Monte Carlo Model (Detail) (Monte Carlo Method [Member])	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Monte Carlo Method [Member]	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Dividend yield	0.00%	0.00%
Volatility	0.00%	53.50%
Risk free interest rate	0.36%	0.36%

Reclassifications_Out_of_Accum2

Reclassifications Out of Accumulated Other Comprehensive Income/(Loss) - Summary of Reclassifications Out of Accumulated Other Comprehensive Loss (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]	'	'	'
Cost of goods sold	($563.60)	($540)	($548)
Income tax expense	-15	-26.4	-3.1
Reclassification Out of Accumulated Other Comprehensive Income [Member]	'	'	'
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]	'	'	'
Total reclassifications	3.7	'	'
Reclassification Out of Accumulated Other Comprehensive Income [Member] | Derivative Instruments [Member]	'	'	'
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]	'	'	'
Cost of goods sold	-0.1	'	'
Total before tax	-0.1	'	'
Income tax expense	0	'	'
Total reclassifications	-0.1	'	'
Reclassification Out of Accumulated Other Comprehensive Income [Member] | Defined Benefit Pension Plan Items [Member]	'	'	'
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]	'	'	'
Amortization of prior service credit	-1.3	'	'
Amortization of actuarial net losses	6.2	'	'
Total before tax	4.9	'	'
Income tax expense	-1.1	'	'
Total reclassifications	$3.80	'	'

Reclassifications_Out_of_Accum3

Reclassifications Out of Accumulated Other Comprehensive Income/(Loss) - Changes in Accumulated Other Comprehensive Loss (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'	'
Opening balance	($152.10)	($102.10)	($115.50)
Other comprehensive income/(loss) before reclassifications	1.2	'	'
Actuarial net losses arising during the year	-6.7	-58.5	19.5
Amounts reclassified from AOCL	3.7	'	'
Net current period other comprehensive income/(loss)	-1.8	'	'
Closing balance	-153.9	-152.1	-102.1
Unrealized Gains/(Losses) on Derivative Instruments [Member]	'	'	'
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'	'
Opening balance	0.1	'	'
Other comprehensive income/(loss) before reclassifications	0	'	'
Amounts reclassified from AOCL	-0.1	'	'
Net current period other comprehensive income/(loss)	-0.1	'	'
Closing balance	0	'	'
Cumulative Translation Adjustments [Member]	'	'	'
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'	'
Opening balance	-34.9	'	'
Other comprehensive income/(loss) before reclassifications	1.2	'	'
Amounts reclassified from AOCL	0	'	'
Net current period other comprehensive income/(loss)	1.2	'	'
Closing balance	-33.7	'	'
Defined Benefit Pension Plan Items [Member]	'	'	'
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'	'
Opening balance	-117.3	'	'
Other comprehensive income/(loss) before reclassifications	0	'	'
Actuarial net losses arising during the year	-6.7	'	'
Amounts reclassified from AOCL	3.8	'	'
Net current period other comprehensive income/(loss)	-2.9	'	'
Closing balance	($120.20)	'	'

Related_Party_Transactions_Add

Related Party Transactions - Additional Information (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Related Party Transactions [Abstract]	'	'	'
Fees payable to Smith, Gambrell & Russell	$1	$0.80	$6.50
Amount due to Smith, Gambrell & Russell	$0.20	'	'