The amount of time after which the restriction on the units will expire.

No definition available.

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- Definition

Element describing the percentage of fair value at which employees may purchase shares of the Company's common stock.

+ References

No definition available.

+ Details

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- Definition

The maximum percentage of employees' annual incentive compensation in restricted stock, which is purchased at a discount to the market, that they may elect to defer.

+ References

No definition available.

+ Details

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- Definition

The intrinsic value of equity-based payment equity instruments, excluding stock (or unit) options, that vested during the reporting period as calculated by applying the disclosed pricing methodology.

+ References

No definition available.

+ Details

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- Definition

Additional information on share-based compensation from continuing operations.

+ References

No definition available.

+ Details

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- Definition

The percentage by which the number of common stock issued will be adjusted upward or downward at the end of the performance period.

+ References

No definition available.

+ Details

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- Definition

Represents the average price of shares issued during the period.

+ References

No definition available.

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Balance Type:	na
Period Type:	duration

- Definition

Represents the number of shares of stock that are reserved for the Company's Employee Stock Purchase Plan.

+ References

No definition available.

+ Details

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Namespace Prefix:	sxi_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Aggregate number of common shares reserved for future issuance.

+ References

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

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Balance Type:	na
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- Definition

Amount of deferred tax expense from write-off of the deferred tax asset related to deductible stock options at exercise.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 20
-Section 55
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=96864182&loc=d3e11283-113907

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Discount rate from fair value on purchase date that participants pay for shares.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Balance Type:	na
Period Type:	duration

- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Paragraph 2
-Subparagraph (c)(2)(i)-(ii)
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Balance Type:	na
Period Type:	instant

- Definition

Number of shares issued during the period as a result of an employee stock purchase plan.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
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Note 13 - Stock-based Compensation and Purchase Plans (Details Textual) - USD ($)	3 Months Ended	12 Months Ended			141 Months Ended
	Jun. 30, 2017	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2015	Mar. 31, 2017
Deferred Tax Expense from Stock Options Exercised		$ 1,900,000	$ 1,800,000	$ 1,300,000
Common Stock, Capital Shares Reserved for Future Issuance	227,986	227,986
Share-based Compensation Continuing Operations		$ 5,023,000	$ 5,089,000	3,764,000
Executive Compensation Plan [Member]
Percent of Participants Annual Incentive Compensation Participants May Elect to Defer Maximum		50.00%
Expiration of Restrictions on Units		3 years
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	35,707	35,707	30,597
Share-based Compensation Continuing Operations		$ 400,000	$ 200,000	300,000
Share-based Compensation Arrangement by Share-based Payment Award Equity Instruments Other than Options Vested in Period Aggregate Intrinsic Value		2,300,000		$ 1,500,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized	$ 300,000	$ 300,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition		1 year 116 days
Executive Compensation Plan [Member] \| Minimum [Member]
Shares of Common Stock Issued Determined by Adjustment of Target Range Percent			50.00%
Executive Compensation Plan [Member] \| Maximum [Member]
Shares of Common Stock Issued Determined by Adjustment of Target Range Percent			200.00%
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Discount from Market Price, Purchase Date	15.00%				5.00%
Percent of Fair Market Value at Which Employees May Purchase Shares of Stock	85.00%
Stock Reserved for Employee Stock Purchase Plan		86,937
Stock Issued During Period, Shares, Employee Stock Purchase Plans		3,742	3,809	3,382
Stock Issued During Period Average Price		$ 84.17	$ 75.66	$ 74.42
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period		51,563	48,984	43,598
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	115,703	115,703	104,525
Share-based Compensation Continuing Operations		$ 3,600,000	$ 2,600,000	$ 2,300,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value		$ 85.07	$ 77.38	$ 76.47
Share-based Compensation Arrangement by Share-based Payment Award Equity Instruments Other than Options Vested in Period Aggregate Intrinsic Value		$ 841,757	$ 1,100,000	$ 2,800,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized	$ 3,400,000	$ 3,400,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition		1 year 160 days
Restricted Stock [Member] \| Executive Compensation Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value		$ 87.05	$ 82.79	$ 80.98
Performance Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period		30,326
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	52,890	52,890	54,736
Performance Stock Units [Member] \| Executive Compensation Plan [Member]
Share-based Compensation Continuing Operations		$ 1,000,000	$ 2,300,000	$ 1,300,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value		$ 83.92	$ 76.61	$ 74.82
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized	$ 1,300,000	$ 1,300,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition		1 year 149 days