Stock Compensation Plan (Details 3) - Restricted Stock [Member] $ in Thousands	Dec. 31, 2016 USD ($)
Unrecognized Compensation Cost Nonvested Awards [Line Items]
2017	$ 107
2018	59
2019	59
2020	35
Total	$ 260

- Definition

Employee service share based compensation on unvested share-based awards, other than options, recognized in next fiscal year following the latest fiscal year.

+ References

No definition available.

+ Details

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

- Definition

Employee service share based compensation on unvested share-based awards, other than options, recognized in the fourth fiscal year following the latest fiscal year.

+ References

No definition available.

+ Details

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

- Definition

Employee service share based compensation on unvested share-based awards, other than options, recognized in the third fiscal year following the latest fiscal year.

+ References

No definition available.

+ Details

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

- Definition

Employee service share based compensation on unvested share-based awards, other than options, recognized in the second fiscal year following the latest fiscal year.

+ References

No definition available.

+ Details

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

- References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
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- Definition

Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

+ References

No definition available.

+ Details

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

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: