The amount of cash payment resulting from the contingent consideration arrangement.

No definition available.

Name:	fii_BusinessAcquisitionContingentConsiderationCashPayment
Namespace Prefix:	fii_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of upfront cash paid to acquire the entity.

+ References

No definition available.

+ Details

Name:	fii_BusinessAcquisitionCostOfAcquiredEntityUpfrontCashPaid
Namespace Prefix:	fii_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The aggregate compensation-related payable relating to various significant employment and incentive arrangements over the remaining terms.

+ References

No definition available.

+ Details

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- Definition

The rate of compounded annual revenue growth necessary in order to have achieved the potential maximum contingent payments.

+ References

No definition available.

+ Details

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- Definition

For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of liability recognized arising from contingent consideration in a business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 35
-Paragraph 1
-Subparagraph b
-URI http://asc.fasb.org/extlink&oid=6911338&loc=d3e6819-128478

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 25
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6911189&loc=d3e6408-128476

+ Details

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

- Definition

The value (monetary amount) of the award the plaintiff seeks in the legal matter.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 9
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14557-108349

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14435-108349

+ Details

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Balance Type:	debit
Period Type:	duration

- Details

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- Details

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Namespace Prefix:
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- Details

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- Details

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Commitments and Contingencies (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended	25 Months Ended
	Dec. 31, 2008	Mar. 31, 2016	Jan. 31, 2014	Dec. 31, 2015	Dec. 01, 2008
Fair value of future consideration payments liability		$ 2,090		$ 2,161
Compensation-related payments in connection with significant employment and incentive arrangements		29,000
Prior Business Acquisition Required Compound Annual Growth Rate to Have Earned Contingent Payments	30.00%
Alleged damages sought		37,000
Other Current Liabilities [Member]
Fair value of future consideration payments liability		700
Other Noncurrent Liabilities [Member]
Fair value of future consideration payments liability		1,400
Clover Capital Acquisition [Member]
Contingent purchase price payments			$ 18,000
Business Acquisition Cost Of Acquired Entity Upfront Cash Paid	$ 30,000
Maximum contingent payments under acquisition agreement					$ 55,000
Series of Individually Immaterial Business Acquisitions [Member] \| Other Liabilities [Member]
Fair value of future consideration payments liability		2,100
Series of Individually Immaterial Business Acquisitions [Member] \| Other Current Liabilities [Member]
Fair value of future consideration payments liability		700
Series of Individually Immaterial Business Acquisitions [Member] \| Other Noncurrent Liabilities [Member]
Fair value of future consideration payments liability		$ 1,400