Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=66004124&loc=d3e637-108580

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14
-URI http://asc.fasb.org/extlink&oid=66004124&loc=d3e681-108580

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14A
-URI http://asc.fasb.org/extlink&oid=66004124&loc=SL7669686-108580

Interest Rate Swaps (Details) - USD ($) $ in Thousands				3 Months Ended		9 Months Ended		12 Months Ended
Interest Rate Swaps (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2016	Sep. 30, 2017	Sep. 24, 2016	Sep. 30, 2017	Sep. 24, 2016	Dec. 31, 2016	Dec. 26, 2015
Derivative [Line Items]
Derivative Asset, Fair Value, Gross Liability	$ 3,134			$ 3,134		$ 3,134		$ 2,817
Derivative Liability, Fair Value, Gross Liability					$ (1,822)		$ (1,822)
Derivative Instruments, Loss Recognized in Other Comprehensive Income (Loss), Effective Portion							(1,822)
Derivative Instruments, Gain Recognized in Other Comprehensive Income (Loss), Effective Portion				59	412	270
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax				0	0			0
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax				0	0	0	0
Derivative Instruments, Gain (Loss) Reclassification from Accumulated OCI to Income, Estimated Net Amount to be Transferred	200
Fair Value, Option, Changes in Fair Value, Gain (Loss)						165	(1,111)	1,392
Other Comprehensive Income (Loss), Net of Tax				36	251	165	(1,111)	1,392
Accumulated Other Comprehensive Income (Loss), Net of Tax	1,557			1,557	(1,111)	1,557	(1,111)	1,392
Derivative Instruments, Loss Recognized in Income, Ineffective Portion and Amount Excluded from Effectiveness Testing				25	306	46	0
Assets Needed for Immediate Settlement, Aggregate Fair Value	0			0		0
Interest Rate Swap Long Term Portion [Member]
Derivative [Line Items]
Other Short-term Borrowings					(1,000)		(1,000)
Derivative Asset	2,940			2,940		2,940		3,215
Interest Rate Swap Short Term Portion [Member]
Derivative [Line Items]
Other Short-term Borrowings					$ (1,000)		$ (1,000)	(398)
Derivative Asset	$ 194			194		194
Beginning Balance [Member]
Derivative [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax								$ 1,392	$ 0
Term Loan 1 [Member]
Derivative [Line Items]
Interest Rate Swap Inception Date			Mar. 31, 2016
Interest Rate Swap Maturity Date	Feb. 19, 2021
Derivative Liability, Notional Amount	$ 182,500		$ 197,500	182,500		182,500
Term Loan 2 [Member]
Derivative [Line Items]
Interest Rate Swap Inception Date		Jun. 30, 2017
Interest Rate Swap Maturity Date	Jun. 15, 2022
Derivative Liability, Notional Amount	$ 98,800	$ 100,000		$ 98,800		$ 98,800