Line of Credit (Detail Textuals) - Line of credit facility - USD ($) $ in Millions			1 Months Ended
Nov. 08, 2017	Nov. 07, 2017	Mar. 30, 2018	Dec. 30, 2016	Dec. 29, 2016	Mar. 31, 2018
Line of Credit Facility [Line Items]
Line of credit facility amount			$ 200			$ 225
Maturity date	Mar. 31, 2018		Mar. 30, 2019
Debt Instrument, Basis Spread on Variable Rate	4.00%		4.00%	3.50%	3.00%
Debt instrument description of variable rate basis	30 day LIBOR		30 day LIBOR	30 day LIBOR	30 day LIBOR
Line of credit facility, floor rate	1.00%		1.00%	1.00%	1.00%
Increased the beneficial ownership limit	30.00%	20.00%	30.00%

Represents the percentage of beneficial ownership limit.

No definition available.

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- Definition

Represents the floor rate related to line of credit facility.

+ References

No definition available.

+ Details

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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- Definition

The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

+ Details

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ 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 210.5-02.22(a)(2))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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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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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ 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 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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- Details

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