Share repurchase program additional authorized amount.

No definition available.

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Namespace Prefix:	mini_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Aggregate dividends declared during the period for each share of common stock outstanding.

+ References

+ Details

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Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

Date the declared dividend will be paid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586

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Balance Type:	na
Period Type:	duration

- Definition

Date the dividend to be paid was declared, in CCYY-MM-DD format.

+ References

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Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

The cash outflow to reacquire common stock during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3291-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

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Balance Type:	credit
Period Type:	duration

- Definition

Amount of stock repurchase plan authorized.

+ References

No definition available.

+ Details

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

- Definition

Amount remaining of a stock repurchase plan authorized.

+ References

No definition available.

+ Details

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

- Definition

Number of shares that have been repurchased during the period and are being held in treasury.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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-Name Accounting Standards Codification
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-Section 50
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-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

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Balance Type:	na
Period Type:	duration

- Details

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Stockholders' Equity - Additional Information (Detail) - USD ($)		3 Months Ended
	Jan. 31, 2018	Mar. 31, 2018	Mar. 31, 2017	Apr. 17, 2015	Nov. 06, 2013
Equity, Class of Treasury Stock [Line Items]
Dividend declared date	Jan. 31, 2018
Cash dividend declared	$ 0.250	$ 0.25	$ 0.23
Dividend payable date	Mar. 14, 2018
Dividend record date (close of business)	Feb. 28, 2018
Share repurchase program authorized amount				$ 175,000,000	$ 125,000,000
Share repurchase program additional authorized amount				$ 50,000,000
Treasury stock value		$ 533,000	$ 7,639,000
Share Repurchase Program
Equity, Class of Treasury Stock [Line Items]
Treasury stock shares acquired		0	200,000
Treasury stock available for repurchase		$ 70,800,000
Treasury stock value			$ 7,000,000
Minimum tax withholding obligations
Equity, Class of Treasury Stock [Line Items]
Treasury stock shares acquired		14,000	21,000
Treasury stock value		$ 500,000	$ 600,000