Debt instrument interest rate percentage of floor on variable rate.

No definition available.

Name:	abcd_DebtInstrumentInterestRatePercentageOfFloorOnVariableRate
Namespace Prefix:	abcd_
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Balance Type:	na
Period Type:	duration

- Definition

Payments for deposits applied to debt retirements, accrued and unpaid interest.

+ References

No definition available.

+ Details

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Balance Type:	credit
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- Definition

Payments for deposits applied to debt retirements, principal amount.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	duration

- 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
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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
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Period Type:	instant

- Definition

Amount of the fee that accompanies borrowing money under the debt instrument.

+ References

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-Name Accounting Standards Codification
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Balance Type:	debit
Period Type:	instant

- Definition

Description of the frequency of periodic payments (monthly, quarterly, annual).

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- Definition

The average effective interest rate during the reporting period.

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- Definition

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

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
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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.

+ References

No definition available.

+ Details

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(2))
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+ Details

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Period Type:	duration

- Definition

Start date of debt instrument redemption period, in CCYY-MM-DD format.

+ References

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Fair value amount of debt instrument that was repurchased.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

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- Definition

Amount of debt issuance costs (for example, but not limited to, legal, accounting, broker, and regulatory fees).

+ References

No definition available.

+ Details

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- Definition

For an unclassified balance sheet, the carrying amount (net of accumulated amortization) as of the balance sheet date of capitalized costs associated with the issuance of debt instruments (for example, legal, accounting, underwriting, printing, and registration costs) that will be charged against earnings over the life of the debt instruments to which such costs pertain.

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- Definition

The cash outflow for the extinguishment of long-term borrowing, with the highest claim on the assets of the entity in case of bankruptcy or liquidation, before its maturity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Glossary Financing Activities
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Balance Type:	credit
Period Type:	duration

- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Period Type:	duration

- Definition

Amount of the cost of borrowed funds accounted for as interest expense for debt.

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-Paragraph 2
-Subparagraph (SX 210.5-03.8)
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- 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.

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-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 19, 20, 22
-Article 5

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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

Period remaining on line of credit facility before it terminates, 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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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
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Balance Type:	credit
Period Type:	instant

- Definition

Cash outflow during the period as a deposit on account for application (deposits to retire or pay down) against an amount of debt owed by the entity.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The cash outflow for incremental, external costs directly pertaining to an early extinguishment of debt, including legal costs and prepayment penalties, and excluding interest and repayment of debt principal.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

+ References

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

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- Details

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- Details

Name:	us-gaap_DebtInstrumentAxis=abcd_AblCreditFacilityMember
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Balance Type:
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- Details

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Period Type:

- Details

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Long-Term Debt (Details Textual) - USD ($)				1 Months Ended	12 Months Ended
Long-Term Debt (Details Textual) - USD ($)	Feb. 15, 2016	Dec. 10, 2015	Mar. 26, 2014	Dec. 31, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Feb. 28, 2011
Debt Instrument [Line Items]
Unamortized discount				$ 1,856,000	$ 1,856,000	$ 277,000
Unamortized deferred financing costs				$ 1,422,000	1,422,000	2,349,000
Loss on extinguishment of debt					4,016,000	922,000
Debt extinguishment other related costs					$ 2,520,000
9.75% Senior Secured Notes Due February 15, 2017
Debt Instrument [Line Items]
Debt instrument, maturity date					Feb. 15, 2017
Unamortized deferred financing costs						$ 2,349,000
Senior secured notes								$ 175,000,000
Senior secured notes, interest rate				9.75%	9.75%	9.75%
Debt instrument, frequency of interest payment					semi-annually in arrears on each February 15th and August 15th
Senior secured notes aggregate principal amount						$ 35,000,000
Amount paid for repurchased senior secured notes						35,000,000
Loss on extinguishment of debt						$ 700,000
Total amount deposited with trustee for debt redemption		$ 146,825,000
Amount deposited with trustee for debt redemption, portion of debt instrument principal amount		140,000,000
Amount deposited with trustee for debt redemption, portion of accrued and unpaid interest		6,825,000
Debt instrument, redemption, effective date					Feb. 15, 2016
9.75% Senior Secured Notes Due February 15, 2017 \| Subsequent Event
Debt Instrument [Line Items]
Loss on extinguishment of debt	$ 4,000,000
Interest paid	2,500,000
Write off of unamortized deferred financing costs and debt discount	1,500,000
Debt extinguishment other related costs	$ 50,000
Revolving Credit Facility
Debt Instrument [Line Items]
Borrowings outstanding				$ 30,000,000	$ 30,000,000
Revolving Credit Facility \| ABL Credit Facility
Debt Instrument [Line Items]
Outstanding borrowings							$ 40,000,000
Loss on extinguishment of debt			$ 200,000
Revolving credit facility, expiration period							4 years
Borrowings outstanding			$ 0
Senior Secured Credit Facility
Debt Instrument [Line Items]
Outstanding borrowings		135,000,000
Debt instrument, maturity date					Dec. 10, 2020
Fees paid to lenders				1,900,000	$ 1,900,000
Unamortized discount				1,900,000	1,900,000
Debt issuance costs					2,300,000
Unamortized deferred financing costs				2,300,000	2,300,000
Senior Secured Credit Facility \| Veronis Suhler Stevenson
Debt Instrument [Line Items]
Fees paid to lenders				$ 1,400,000	$ 1,400,000
Senior Secured Credit Facility \| LIBOR loans
Debt Instrument [Line Items]
Percentage of floor on variable interest rate					1.00%
Senior Secured Credit Facility \| Term Loan A
Debt Instrument [Line Items]
Outstanding borrowings		70,000,000
Interest rate applied				5.50%
Senior Secured Credit Facility \| Term Loan A \| LIBOR loans
Debt Instrument [Line Items]
Debt instrument, interest rate, applicable margin					3.75%
Senior Secured Credit Facility \| Term Loan A \| Base Rate loans
Debt Instrument [Line Items]
Debt instrument, interest rate, applicable margin					2.75%
Senior Secured Credit Facility \| Term Loan B
Debt Instrument [Line Items]
Outstanding borrowings		35,000,000
Interest rate applied				6.25%
Senior Secured Credit Facility \| Term Loan B \| LIBOR loans
Debt Instrument [Line Items]
Debt instrument, interest rate, applicable margin					5.25%
Senior Secured Credit Facility \| Term Loan B \| Base Rate loans
Debt Instrument [Line Items]
Debt instrument, interest rate, applicable margin					4.25%
Senior Secured Credit Facility \| Revolving Credit Facility
Debt Instrument [Line Items]
Outstanding borrowings		$ 30,000,000
Interest rate applied				5.50%
Unused line fee					0.50%
Unamortized deferred financing costs				$ 900,000	$ 900,000
Senior Secured Credit Facility \| Revolving Credit Facility \| LIBOR loans
Debt Instrument [Line Items]
Debt instrument, interest rate, applicable margin					4.50%
Senior Secured Credit Facility \| Revolving Credit Facility \| Base Rate loans
Debt Instrument [Line Items]
Debt instrument, interest rate, applicable margin					3.50%
Senior Secured Credit Facility \| Term Loan A and Term Loan B
Debt Instrument [Line Items]
Unamortized deferred financing costs				$ 1,400,000	$ 1,400,000
Swing Line Loan Sub Facility \| Revolving Credit Facility \| ABL Credit Facility
Debt Instrument [Line Items]
Outstanding borrowings							$ 5,000,000
Letter Of Credit Sub Facility \| Revolving Credit Facility \| ABL Credit Facility
Debt Instrument [Line Items]
Outstanding borrowings							$ 5,000,000