Organization and Summary of Significant Accounting Policies (Organization and Revenue Recognition) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2016	Sep. 18, 2013
Revenue Recognition
Lease rent to be received, more than 30 days past due	$ 3.6
Maintenance reserve payments to be received, more than 30 days past due	$ 2.4
Minimum number of days for which lease rent and maintenance reserve payments are past due	30 days
Other Revenue, Net	$ 4.0
WOLF
Organizations [Line Items]
Previously held interest (as a percent)	50.00%
Acquisition of the remaining outstanding shares (as a percent)	100.00%	50.00%

Percentage of voting equity interests acquired at the acquisition date in the business combination.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=65885119&loc=d3e1392-128463

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- Definition

Percentage of equity in the acquiree held by the acquirer immediately before the acquisition date in a business combination.

+ References

No definition available.

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- Definition

Amount, after sales adjustments, returns, allowances, and discounts, of revenue classified as other.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1(a),(d))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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- References

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- Definition

Represents the minimum number of days for which lease rent and maintenance reserve payments are past due.

+ References

No definition available.

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- Definition

Represents the amount of maintenance reserve payments receivable that are more than 30 days past due.

+ References

No definition available.

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- Definition

Represents the amount of lease rent receivables that are more than 30 days past due.

+ References

No definition available.

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- Definition

Organization [Line Items]

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