Derivatives (Derivatives - Fair Value and Designation) (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 30, 2017
Derivative Asset, Fair Value, Net [Abstract]
Interest rate swaps	$ 196	$ 0
Derivative Liability, Fair Value, Net [Abstract]
Interest rate swaps	861	2,229
Designated as Hedging Instrument [Member] \| Interest Rate Swap [Member] \| Prepaid Expenses and Other Current Assets [Member]
Derivative Asset, Fair Value, Net [Abstract]
Interest rate swaps	2	0
Designated as Hedging Instrument [Member] \| Interest Rate Swap [Member] \| Other Assets [Member]
Derivative Asset, Fair Value, Net [Abstract]
Interest rate swaps	194	0
Designated as Hedging Instrument [Member] \| Interest Rate Swap [Member] \| Accrued Liabilities [Member]
Derivative Liability, Fair Value, Net [Abstract]
Interest rate swaps	449	842
Designated as Hedging Instrument [Member] \| Interest Rate Swap [Member] \| Other Liabilities [Member]
Derivative Liability, Fair Value, Net [Abstract]
Interest rate swaps	$ 412	$ 1,387

Fair value, after offset of derivative asset, of financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, elected not to be and before offset against a right to receive collateral under a master netting arrangement. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=d3e41678-113959

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226006-175313

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313

Name:	us-gaap_DerivativeFairValueOfDerivativeLiabilityAmountNotOffsetAgainstCollateral
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant