Business Combination (Schedule Of Net Assets Acquired) (Details) (USD $) In Thousands	Sep. 30, 2011	Jul. 08, 2011
Business Combination [Abstract]
Cash and cash equivalents		$ 12,871
Account receivable		12,862
Other receivables		1,712
Other current assets		2,265
Property and equipment, net		4,066
Other non-current assets		5,113
Accounts payable		(1,329)
Accrued liabilities		(12,412)
Deferred revenue liability		(10,048)
Other non-current liabilities	5,900	3,093
Total net assets acquired		$ 12,007

Business acquisition, purchase price allocation, current assets, other receivables

Name:	trmb_BusinessAcquisitionPurchasePriceAllocationCurrentAssetsOtherReceivables
Namespace Prefix:	trmb
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The total purchase price of the acquired entity. This includes cash paid to equity interest holders of the acquired entity, fair value of debt and equity securities issued to equity holders of the acquired entity, and transaction costs paid to third parties to consummate the acquisition.

+ References

+ Details

Name:	us-gaap_BusinessAcquisitionPurchasePriceAllocationAssetsAcquiredLiabilitiesAssumedNet
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The amount of cash and cash equivalents acquired in a business combination.

+ References

+ Details

Name:	us-gaap_BusinessAcquisitionPurchasePriceAllocationCurrentAssetsCashAndCashEquivalents
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The amount of acquisition cost of a business combination allocated to prepaid expenses and other current assets. Does not include amounts allocated to cash and cash equivalents, marketable securities, receivables, inventory, and assets not to be used.

+ References

+ Details

Name:	us-gaap_BusinessAcquisitionPurchasePriceAllocationCurrentAssetsPrepaidExpenseAndOtherAssets
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The amount of acquisition cost of a business combination allocated to receivables.

+ References

+ Details

Name:	us-gaap_BusinessAcquisitionPurchasePriceAllocationCurrentAssetsReceivables
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The amount of acquisition cost of a business combination allocated to accounts payable of the acquired entity.

+ References

+ Details

Name:	us-gaap_BusinessAcquisitionPurchasePriceAllocationCurrentLiabilitiesAccountsPayable
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The amount of acquisition cost of a business combination allocated to accrued expenses of the acquired entity.

+ References

+ Details

Name:	us-gaap_BusinessAcquisitionPurchasePriceAllocationCurrentLiabilitiesAccruedLiabilities
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The amount of acquisition cost of a business combination allocated to deferred revenue of the acquired entity.

+ References

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

-Publisher FASB

-Name Emerging Issues Task Force (EITF)

-Number 01-3

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

Name:	us-gaap_BusinessAcquisitionPurchasePriceAllocationCurrentLiabilitiesDeferredRevenue
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The amount of acquisition cost of a business combination allocated to noncurrent assets of the acquired entity, except for property plant and equipment, intangible assets, and goodwill.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 51

-Subparagraph e

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Emerging Issues Task Force (EITF)

-Number 98-1

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 37

-Subparagraph f

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

Name:	us-gaap_BusinessAcquisitionPurchasePriceAllocationOtherNoncurrentAssets
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The amount of acquisition cost of a business combination allocated to other noncurrent liabilities of the acquired entity.

+ References

+ Details

Name:	us-gaap_BusinessAcquisitionPurchasePriceAllocationOtherNoncurrentLiabilities
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The amount of acquisition cost of a business combination allocated to property, plant and equipment to be used in ongoing operations.

+ References

+ Details

Name:	us-gaap_BusinessAcquisitionPurchasePriceAllocationPropertyPlantAndEquipment
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	us-gaap_BusinessCombinationsAbstract
Namespace Prefix:	us-gaap
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration