Note 15 - Income Taxes (Details) - Summary of Effective Income Tax Rate Reconciliation	3 Months Ended	6 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2013
Reconciliation to effective tax rate:
Provision for income taxes at the anticipated annual tax rate	36.10%	40.60%	41.00%	37.90%
Impact of foreign operations		(1.80%)	(0.20%)	(1.00%)
Enactment of tax law changes	(6.10%)lyts_EnactmentOfTaxLawChanges		(2.90%)lyts_EnactmentOfTaxLawChanges
Valuation allowances		7.90%		2.80%
Uncertain tax positions	(1.30%)	(4.10%)	(1.20%)	(2.90%)
Other	(0.30%)	(0.60%)	(2.40%)
Effective tax rate	28.40%	42.00%	34.30%	36.80%

The effective income tax percentage for income taxes at the anticipated annual tax rate.

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The impact of tax law changes including federal tax credits on the effective tax rate.

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to changes in the valuation allowance for deferred tax assets.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to statutory income tax expense (benefit) outside of the country of domicile.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to income tax contingencies. Includes, but not limited to, domestic tax contingency, foreign tax contingency, state and local tax contingency, and other contingencies.

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