Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 30, 2015	Mar. 31, 2014
Cash flows from operating activities:
Net loss	$ (4,315)	$ (3,126)
Adjustments to reconcile net loss to net cash used in operating activities
Depreciation and amortization	580us-gaap_DepreciationAndAmortization	639us-gaap_DepreciationAndAmortization
Debt discount amortization	165	0
Loss on sale of fixed assets	18us-gaap_GainLossOnDispositionOfAssets	0us-gaap_GainLossOnDispositionOfAssets
Provision for bad debts	76us-gaap_ProvisionForDoubtfulAccounts	(11)us-gaap_ProvisionForDoubtfulAccounts
Provision for lease terminations reserves	51cosi_LeaseTerminationAccrual	(16)cosi_LeaseTerminationAccrual
Stock-based compensation expense	108us-gaap_ShareBasedCompensation	168us-gaap_ShareBasedCompensation
Interest expense paid in kind	256us-gaap_PaidInKindInterest	0us-gaap_PaidInKindInterest
Changes in operating assets and liabilities:
Credit card receivable	(917)	(157)
Accounts receivable	(287)	5
Inventories	92us-gaap_IncreaseDecreaseInInventories	(10)us-gaap_IncreaseDecreaseInInventories
Prepaid expenses and other current assets	250	212
Other assets	(1)	16
Accounts payable and accrued expenses	(1,762)	(814)
Deferred revenue	(17)	0
Other long-term liabilities	(247)	(85)
Net cash used in operating activities	(5,950)	(3,179)
Cash flows from investing activities:
Capital expenditures	(1,225)	(186)
Net cash used in investing activities	(1,225)	(186)
Net decrease in cash and cash equivalents	(7,175)	(3,365)
Cash and cash equivalents, beginning of period	21,053	5,614
Cash and cash equivalents, end of period	13,878	2,249
Cash paid for:
Corporate franchise and income taxes	$ 32cosi_CorporateFranchiseAndIncomeTaxes	$ 23cosi_CorporateFranchiseAndIncomeTaxes

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Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.

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Amount of cash inflow (outflow) of investing activities, excluding discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.

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Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period).

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