Nominal or face amount used to calculate payments on the derivative asset.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1B

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1A

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5579245-113959

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Notional Amount

-URI http://asc.fasb.org/extlink&oid=6519104

+ Details

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- Definition

Cap rate on an interest rate derivative such as an interest rate cap or collar. If market rates exceed the cap rate, a payment or receipt is triggered on the contract.

+ References

No definition available.

+ Details

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- Definition

Fixed interest rate related to the interest rate derivative.

+ References

No definition available.

+ Details

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- Definition

The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

+ References

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- Definition

Nominal or face amount used to calculate payments on the derivative liability.

+ References

+ Details

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- Definition

Amount of gain (loss) from the ineffectiveness of the hedge.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4C

-Subparagraph (d)(1)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 25

-Section 50

-Paragraph 1

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6886632&loc=d3e76258-113986

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- Definition

Period remaining until the derivative contract matures, 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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Balance Type:	na
Period Type:	duration

- Definition

Number of monthly interest payments required under an equipment financing arrangement.

+ References

No definition available.

+ Details

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

- Definition

Number of monthly interest payments, which are protected against the variability in expected future cash flows attributable to changes in the benchmark interest rate.

+ References

No definition available.

+ Details

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Namespace Prefix:	wlt_
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- Details

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Derivative Financial Instruments (Details) (USD $)	0 Months Ended	12 Months Ended	0 Months Ended
Derivative Financial Instruments (Details) (USD $)	Jun. 27, 2011	Dec. 31, 2014	Dec. 30, 2008
Interest rate swap - June 2011
Fair Value of Financial Instruments
Derivative liability, notional amount	$ 450,000,000
Agreement period	3 years
Fixed rate (as a percent)	1.17%
Interest rate swap - June 2011 \| Interest Expense
Fair Value of Financial Instruments
Amount recognized in Statements of Operations, effective portion		1,100,000
Interest rate swap - June 2011 \| Other Income (loss)
Fair Value of Financial Instruments
Amount recognized in Statements of Operations, ineffective portion		300,000
Interest rate swap - December 2008
Fair Value of Financial Instruments
Derivative liability, notional amount			31,500,000
Agreement period			62 months
Fixed rate (as a percent)			1.84%
Number of monthly interest payments, hedged			62 months
Number of monthly interest payments			64 months
Interest rate cap
Fair Value of Financial Instruments
Agreement period	3 years
Derivative asset, notional amount	$ 255,000,000
Fixed rate (as a percent)	2.00%