Goodwill and Intangible Assets - Intangible Assets and Related Accumulated Amortization (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Finite-Lived Intangible Assets [Line Items]
Cost	$ 776,775	$ 761,047
Accumulated Amortization	(370,299)	(313,429)
Total	406,476us-gaap_FiniteLivedIntangibleAssetsNet	447,618us-gaap_FiniteLivedIntangibleAssetsNet
Technology-based [Member]
Finite-Lived Intangible Assets [Line Items]
Weighted Average Useful Life	8 years	8 years
Cost	299,705	294,940
Accumulated Amortization	(195,698)	(180,581)
Total	104,007	114,359
Marketing-related [Member]
Finite-Lived Intangible Assets [Line Items]
Weighted Average Useful Life	5 years	5 years
Cost	71,504	71,047
Accumulated Amortization	(54,745)	(44,274)
Total	16,759	26,773
Contract-based [Member]
Finite-Lived Intangible Assets [Line Items]
Weighted Average Useful Life	6 years	6 years
Cost	6,555	6,555
Accumulated Amortization	(6,555)	(6,555)
Total	0	0
Customer-related [Member]
Finite-Lived Intangible Assets [Line Items]
Weighted Average Useful Life	13 years	13 years
Cost	399,011	388,505
Accumulated Amortization	(113,301)	(82,019)
Total	$ 285,710	$ 306,486

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

+ Details

Name:	us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

+ Details

Name:	us-gaap_FiniteLivedIntangibleAssetsGross
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	us-gaap_FiniteLivedIntangibleAssetsLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

+ Details

Name:	us-gaap_FiniteLivedIntangibleAssetsNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	us-gaap_FiniteLivedIntangibleAssetUsefulLife
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=us-gaap_ContractualRightsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=us-gaap_CustomerRelationshipsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=vrsk_MarketingRelatedMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=vrsk_TechnologyBasedMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: