Business Acquisitions (Details) (USD $)	9 Months Ended
Sep. 30, 2011
Business Acquisition [Line Items]
Cost of Acquired Entity Transaction Costs	$ 1,300,000
Northern Digital, Inc Acquisition [Member]
Business Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition	2011-06-03
Description of Acquired Entity	a leading provider of 3-D measurement technology for medical applications in computer-assisted surgery and computer-assisted therapy
Name of Acquired Entity	Northern Digital, Inc.
Reason for Business Combination	Roper acquired NDI as an addition to its medical platform
Cost of Acquired Entity Purchase Price	205,000,000
Purchase Price Allocation Goodwill Amount	135,000,000
Purchase Price Allocation Intangible Assets Amount	23,000,000
United Controls Groups [Member]
Business Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition	2011-09-26
Description of Acquired Entity	a provider of control systems in the oil and gas industry
Name of Acquired Entity	United Controls Group, Inc.
Reason for Business Combination	UCG was acquired as an addition to Roper's existing control systems businesses
Cost of Acquired Entity Purchase Price	23,000,000
Purchase Price Allocation Goodwill Amount	$ 74,000,000

Identifiable intangible asset (an asset that lacks physical substance, but not a financial asset) acquired in a business combination. Does not include goodwill.

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Namespace Prefix:	rop
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The total cost of the acquired entity including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, the fair value of the liabilities assumed, and direct costs of the acquisition.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 51

-Subparagraph d

+ Details

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

- Definition

Amount of direct costs of the business combination including legal, accounting, and other costs incurred to consummate the business acquisition.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 51

-Subparagraph d

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 24

+ Details

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

- Definition

With respect to a business combination completed during the period, this element provides a description of the business, other than the name, which may include the industry, size, products and other important information.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141R

-Paragraph 68

-Subparagraph a

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 51

-Subparagraph a

+ Details

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

- Definition

Month, date and year when the results of operations of the acquired entity began to be included in the income statement of the combined entity. For disclosure purposes, the effective date of an acquisition equates to the acquisition date, when acquisition date is defined as the date on which the acquirer obtained control of the acquired entity. The effective date of an acquisition may be either earlier or later than the date on which the acquisition agreement was executed (closed).

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141R

-Paragraph 10, 11

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141R

-Paragraph 3

-Subparagraph c

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141R

-Paragraph 68

-Subparagraph b

+ Details

Name:	us-gaap_BusinessAcquisitionEffectiveDateOfAcquisition
Namespace Prefix:	us-gaap
Data Type:	us-types:dateStringItemType
Balance Type:	na
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ Details

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

- Definition

Name of the acquired entity.

+ References

+ Details

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

- Definition

Amount of goodwill arising from a business combination, which is the excess of the cost of the acquired entity over the amounts assigned to assets acquired and liabilities assumed.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 52

-Subparagraph c

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 53

-Subparagraph d

+ Details

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

- Definition

This element represents a description of the primary reason for the business combination which may consist of general categories such as top-line growth, synergistic benefits, market share, and diversification and the more detailed factors that might apply.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 51

-Subparagraph b

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141R

-Paragraph 68

-Subparagraph d

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration