Fair Value Disclosure (On a Recurring Basis) (Details) - Fair value measurements, recurring - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Level 1
Assets:
Available for sale securities	$ 8,715	$ 7,882
Assets at fair value	8,715	7,882
Liabilities:
Interest rate swap agreements	0	0
Liabilities at fair value	0	0
Level 2
Assets:
Available for sale securities	0	0
Assets at fair value	0	0
Liabilities:
Interest rate swap agreements	3	339
Liabilities at fair value	3	339
Level 3
Assets:
Available for sale securities	0	0
Assets at fair value	0	0
Liabilities:
Interest rate swap agreements	0	0
Liabilities at fair value	0	0
Total
Assets:
Available for sale securities	8,715	7,882
Assets at fair value	8,715	7,882
Liabilities:
Interest rate swap agreements	3	339
Liabilities at fair value	$ 3	$ 339

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=75030427&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27232-111563

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82896770&loc=d3e26610-111562

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Fair value as of the balance sheet date of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as liabilities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13433-108611

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Fair value of financial and nonfinancial obligations.

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