Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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- Definition

Represents the portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments representing the amount excluded from the assessment of hedge effectiveness.

+ References

No definition available.

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- Definition

Derivative Instruments, Gain (Loss) Recognized in Income, Ineffective Portion

+ References

No definition available.

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- Definition

Represents the number of derivative agreements entered into by the entity during the reporting period.

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- Definition

Fixed interest rate related to the interest rate derivative.

+ References

No definition available.

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- Definition

Estimated period for the anticipated transfer of gain (loss), net, from accumulated other comprehensive income into earnings, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959

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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.

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No definition available.

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Derivative Financial Instruments - General Information (Details)	3 Months Ended		12 Months Ended
	Dec. 31, 2017 USD ($)	Dec. 29, 2013 agreement	Oct. 01, 2017 USD ($)	Sep. 29, 2013 agreement
Interest rate swap agreements \| Designated as cash flow hedges \| Derivatives designated as hedging instruments
Derivative Financial Instruments
Number of derivative agreements \| agreement		2		3
Amount of effective portion of derivatives before tax effect	$ 100,000
Period of reclassification from accumulated other comprehensive income (loss) to interest expense	12 months
Foreign currency forward contracts and interest rate swap agreements \| Derivatives designated as hedging instruments
Derivative Financial Instruments
Ineffective portion of derivative instruments	$ 0		$ 0
Amounts excluded from effectiveness testing	0		$ 0
Interest rate swap agreement bearing fixed rate 1.36%
Derivative Financial Instruments
Notional Amount	$ 39,398,000
Fixed Rate (as a percent)	1.36%
Interest rate swap agreement bearing fixed rate 1.34%
Derivative Financial Instruments
Notional Amount	$ 39,398,000
Fixed Rate (as a percent)	1.34%
Interest rate swap agreement bearing fixed rate 1.35%
Derivative Financial Instruments
Notional Amount	$ 39,398,000
Fixed Rate (as a percent)	1.35%
Interest rate swap agreement bearing fixed rate 1.23%
Derivative Financial Instruments
Notional Amount	$ 19,700,000
Fixed Rate (as a percent)	1.23%
Interest rate swap agreement bearing fixed rate 1.24%
Derivative Financial Instruments
Notional Amount	$ 19,700,000
Fixed Rate (as a percent)	1.24%