Stock Based Compensation (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2014
Stock-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	$ 223,000
Minimum [Member]
Stock-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation arrangement, expected dividend rate (in hundredths)	0.00%
Maximum [Member]
Stock-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation arrangement, expected dividend rate (in hundredths)	5.00%
Stock Options [Member]
Stock-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation, shares granted options to purchase (in shares)	24,576
Exercise price of stock options granted (in dollars per share)	$ 5.82
Percentage of shares vested on first anniversary of the grant date (in hundredths)	30.00%
Percentage of shares vested on second anniversary of the grant date (in hundredths)	30.00%
Percentage of shares vested on third anniversary of the grant date (in hundredths)	40.00%
Stock option, expiration date	Mar. 13, 2019
Grant date fair value	$ 1.88

Stock option grant date fair value

No definition available.

Name:	lgl_GrantDateFairValue
Namespace Prefix:	lgl_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

Refers to the percentage of shares vested on grant date year one.

+ References

No definition available.

+ Details

Name:	lgl_PercentageOfSharesVestedOnGrantDateYearOne
Namespace Prefix:	lgl_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Refers to the percentage of shares vested on grant date year three.

+ References

No definition available.

+ Details

Name:	lgl_PercentageOfSharesVestedOnGrantDateYearThree
Namespace Prefix:	lgl_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Refers to the percentage of shares vested on grant date year two.

+ References

No definition available.

+ Details

Name:	lgl_PercentageOfSharesVestedOnGrantDateYearTwo
Namespace Prefix:	lgl_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Aggregate unrecognized cost of option awards made to employees under a stock option plan or plans, that have yet to vest.

+ References

No definition available.

+ Details

Name:	us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Date the equity-based award expires, in CCYY-MM-DD format.

+ References

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardExpirationDate
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (f)(2)(iii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph e(2)(c)

-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_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance on stock options awarded.

+ References

No definition available.

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration