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The number of hours an employee must provide service to the Company each year in order to be eligible to receive employer matching contributions.

No definition available.

Name:	fhi_DefinedContributionPlanAnnualVestingEmployeeServicePeriod
Namespace Prefix:	fhi_
Data Type:	xbrli:durationItemType
Balance Type:	na
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The number of years an employee must provide service to the Company in order to be eligible to receive employer matching contributions.

No definition available.

Name:	fhi_DefinedContributionPlanEmployeeServiceVestingPeriod
Namespace Prefix:	fhi_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Defined Contribution Plan Number Of Shares Of Class B Common Stock Purchased Under Plan During Current Year

No definition available.

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Namespace Prefix:	fhi_
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Employee Stock Purchase Plans, Maximum Annual Contributions Per Employee, Percent

No definition available.

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Data Type:	num:percentItemType
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Employee Stock Purchase Plans, Number Of Shares Authorized

No definition available.

Name:	fhi_EmployeeStockPurchasePlansNumberOfSharesAuthorized
Namespace Prefix:	fhi_
Data Type:	xbrli:sharesItemType
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The total number of shares of Class B common stock purchased under the employee stock purchase plan since inception.

No definition available.

Name:	fhi_EmployeeStockPurchasePlansNumberOfSharesPurchasedUnderPlanSinceInception
Namespace Prefix:	fhi_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

Amount of cost for defined contribution plan.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

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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.

No definition available.

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Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

No definition available.

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Data Type:	num:percentItemType
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Percentage employer matches of the employee's percentage contribution matched.

No definition available.

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Data Type:	num:percentItemType
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Percentage of employer's matching contributions to a defined contribution plan that vests in a given year.

No definition available.

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Data Type:	num:percentItemType
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Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan.

No definition available.

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
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