Name:	hmg_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingAndExercisableNumberAggregateIntrinsic
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Represents share based compensation arrangement by share based payment award options vested and expected to vest outstanding and exercisable number, aggregate intrinsic value.

No definition available.

Name:	hmg_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingAndExercisableNumberAggregateIntrinsicValue
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Data Type:	xbrli:sharesItemType
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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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Data Type:	xbrli:sharesItemType
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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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Data Type:	num:perShareItemType
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Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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Data Type:	xbrli:sharesItemType
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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Net number of share options (or share units) granted during the period.

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Gross number of share options (or share units) granted during the period.

No definition available.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Data Type:	num:perShareItemType
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Number of options outstanding, including both vested and non-vested options.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Data Type:	num:perShareItemType
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Period Type:	instant

- References

No definition available.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

No definition available.

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Data Type:	num:perShareItemType
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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

No definition available.

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Data Type:	num:perShareItemType
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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

No definition available.

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Data Type:	num:perShareItemType
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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

No definition available.

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Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
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Number of share options (or share units) exercised during the current period.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644