Debt Instrument, Minimum Restricted Cash Balance

No definition available.

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Balance Type:	credit
Period Type:	instant

- Definition

Debt Instrument, Number of Periods to Compute Interest on Notes

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt Instrument, Percentage of Net proceeds from Issuance or Sale of Equity

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Debt Instrument, Percentage of Net proceeds from Issuance or Sale of Equity in the Event of a Default

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Debt Instrument, Percentage of Payable in Arrears

+ References

No definition available.

+ Details

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Namespace Prefix:	rsys_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt Instrument, Percentage of Total Revolving Loan Commitment to be Paid

+ References

No definition available.

+ Details

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Namespace Prefix:	rsys_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt Instrument, Period to Compute Interest

+ References

No definition available.

+ Details

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Namespace Prefix:	rsys_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt Instrument, Period to Compute Interest on Notes

+ References

No definition available.

+ Details

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Namespace Prefix:	rsys_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Repayments of Debt Issuance Fees

+ References

No definition available.

+ Details

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Namespace Prefix:	rsys_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Exercise price per share or per unit of warrants or rights outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i)(4))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of warrants or rights outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- 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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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph e
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of unamortized debt discount (premium) and debt issuance costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28555-108399

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ 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))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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

- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- 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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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- 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

+ Details

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

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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

- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

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Period Type:

- Details

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Balance Type:
Period Type:

- Details

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- Details

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Balance Type:
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- Details

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- Details

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- Details

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Balance Type:
Period Type:

- Details

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- Details

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Debt and Credit Agreements Debt and Credit Agreements - Narrative (Details)			3 Months Ended	9 Months Ended	12 Months Ended		24 Months Ended
	Feb. 28, 2019 USD ($)	Jan. 03, 2018 USD ($) performance_period $ / shares shares	Mar. 31, 2019 USD ($)	Sep. 30, 2018 USD ($)	Jan. 02, 2021	Dec. 31, 2017 USD ($)	Jan. 03, 2020
Line of Credit Facility [Line Items]
Outstanding balance				$ 11,989,000		$ 16,000,000
Class of warrant outstanding (in shares) \| shares		6,006,667
Price per share (in usd per share) \| $ / shares		$ 1.00
Revolving Credit Facility
Line of Credit Facility [Line Items]
Debt instrument, term		3 years
Maximum borrowing capacity		$ 30,000,000.0
Unamortized debt issuance costs		200,000
Revolving Credit Facility \| ABL Credit Agreement
Line of Credit Facility [Line Items]
Maximum borrowing capacity		$ 20,000,000.0
Percentage payable in arrears		1.00%
Debt instrument, interest rate, stated percentage		2.00%
Commitment fee percentage		0.375%
Percentage of total revolving loan commitment to be paid						2.00%
Minimum restricted cash balance				4,000,000
Repayments of debt issuance fees		$ 300,000
Outstanding balance				11,989,000		$ 16,000,000
Remaining borrowing capacity				$ 3,400,000
Revolving Credit Facility \| ABL Credit Agreement \| Scenario, Forecast
Line of Credit Facility [Line Items]
Percentage of total revolving loan commitment to be paid							1.00%
Revolving Credit Facility \| ABL Credit Agreement \| London Interbank Offered Rate (LIBOR)
Line of Credit Facility [Line Items]
Basis spread on variable interest rate		2.00%
Revolving Credit Facility \| Note Purchase Agreement
Line of Credit Facility [Line Items]
Maximum borrowing capacity		$ 17,000,000.0
Debt instrument, interest rate, stated percentage		4.50%		5.00%
Minimum restricted cash balance				$ 4,000,000
Period to compute interest on notes		360 days
Number of periods to compute interest on notes \| performance_period		12
Period to compute interest		30 days
Percentage of net proceeds from issuance or sale of equity		33.00%
Percentage of net proceeds from issuance or sale of equity in the event of a default		100.00%
Redemption price, percentage						5.00%
Revolving Credit Facility \| Note Purchase Agreement \| Scenario, Forecast
Line of Credit Facility [Line Items]
Repayments of debt	$ 4,500,000		$ 1,500,000
Redemption price, percentage					3.00%
Revolving Credit Facility \| Note Purchase Agreement \| London Interbank Offered Rate (LIBOR)
Line of Credit Facility [Line Items]
Basis spread on variable interest rate				11.00%
Revolving Credit Facility \| Note Purchase Agreement \| Prime Rate
Line of Credit Facility [Line Items]
Basis spread on variable interest rate		5.75%
Letter of Credit \| Revolving Credit Facility \| ABL Credit Agreement
Line of Credit Facility [Line Items]
Maximum borrowing capacity		$ 1,500,000.0
Common Stock
Line of Credit Facility [Line Items]
Class of warrant outstanding (in shares) \| shares		6,006,667
Price per share (in usd per share) \| $ / shares		$ 1.00
Senior Notes [Member] \| Note Purchase Agreement
Line of Credit Facility [Line Items]
Debt Issuance Costs, Gross		$ 2,100,000