Long-Term Debt (Debt Covenants And Credit Facility) (Details) (USD $)	12 Months Ended
Dec. 31, 2014
Debt Instrument [Line Items]
Number of credit rating agencies	2wlk_NumberofCreditRatingAgencies
Maximum unrestricted distributions allowable	$ 100,000,000
Senior Secured Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Covenant Terms, Acquisitions Restrictions, Borrowing Availability Threshold, Percent Of Commitments, Scenario Two	100.00%
Borrowing availability of bank commitments, minimum	50,000,000
Line of Credit Facility, Covenant Terms, Acquisitions And Investments, Borrowing Availability Threshold, Percent Of Commitments, Scenario Two	12.50%
Line of Credit Facility, Covenant Terms, Specified Investments Permissible	50,000,000
Line of Credit Facility, Covenant Terms, Specified Investments Permissible, Percentage Of Tangible Assets And Acquisitions	1.25%
Line of Credit Facility, Covenant Terms, Specified Acquisitions Permissible	100,000,000
Line of Credit Facility, Covenant Terms, Specified Acquisitions Permissible, Percentage Of Tangible Assets	2.50%
Debt Covenant [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Maximum unrestricted quarterly dividends allowable under debt covenants	$ 0.10
Maximum percentage of income distribution	50.00%
Maximum distribution percentage of specified net cash proceeds	100.00%
Minimum [Member] \| Senior Secured Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Covenant Terms, Distributions Restrictions, Borrowing Availability Threshold, Scenario Two	50,000,000
Line of Credit Facility, Covenant Terms, Acquisitions Restrictions, Borrowing Availability Threshold, Percent Of Commitments, Scenario One	15.00%
Maximum [Member] \| Senior Secured Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Covenant Terms, Distributions Restrictions, Borrowing Availability Threshold, Scenario Two	$ 60,000,000
Maximum [Member] \| Debt Covenant [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Fixed charge coverage ratio for debt covenant	2.0

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- Definition

The calculated fixed charge coverage ratio.

+ References

No definition available.

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- Definition

Line of Credit Facility, Covenant Terms, Acquisitions And Investments, Borrowing Availability Threshold, Percent Of Commitments, Scenario Two

+ References

No definition available.

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- Definition

Line of Credit Facility, Covenant Terms, Acquisitions And Investments, Borrowing Availability Threshold, Scenario Two

+ References

No definition available.

+ Details

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- Definition

Line of Credit Facility, Covenant Terms, Acquisitions Restrictions, Borrowing Availability Threshold, Percent Of Commitments, Scenario One

+ References

No definition available.

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- Definition

Line of Credit Facility, Covenant Terms, Acquisitions Restrictions, Borrowing Availability Threshold, Fixed Coverage Ratio, Scenario Two

+ References

No definition available.

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- Definition

Line of Credit Facility, Covenant Terms, Acquisitions Restrictions, Borrowing Availability Threshold, Scenario One

+ References

No definition available.

+ Details

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- Definition

Line of Credit Facility, Covenant Terms, Specified Acquisitions Permissible

+ References

No definition available.

+ Details

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- Definition

Line of Credit Facility, Covenant Terms, Specified Acquisitions Permissible, Percentage Of Tangible Assets

+ References

No definition available.

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- Definition

Line of Credit Facility, Covenant Terms, Specified Investments Permissible

+ References

No definition available.

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- Definition

Line of Credit Facility, Covenant Terms, Specified Investments Permissible, Percentage Of Tangible Assets And Acquisitions

+ References

No definition available.

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- Definition

Maximum distribution percentage of specified net cash proceeds received after a stated period plus other adjustments, and subject to certain other distribution terms.

+ References

No definition available.

+ Details

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- Definition

Maximum percentage of income distribution, subject to certain other distribution terms.

+ References

No definition available.

+ Details

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- Definition

The maximum unrestricted distribution allowed under debt covenants. Distributions in excess of this amount are subject to certain restrictions.

+ References

No definition available.

+ Details

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- Definition

The maximum unrestricted payment per share allowed under debt covenants for the quarterly dividend.

+ References

No definition available.

+ Details

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- Definition

Number of Credit Rating Agencies

+ References

No definition available.

+ Details

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