Fair Values (Schedule of Fair Value Measurement) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Mar. 31, 2018
Recurring basis \| Quoted market prices in active markets (Level 1)
Assets and liabilities recorded at fair value
Net Carrying Value	$ 0	$ 0
Recurring basis \| Significant unobservable inputs (Level 3)
Assets and liabilities recorded at fair value
Net Carrying Value	22,842	21,835
Non-recurring basis \| Quoted market prices in active markets (Level 1)
Assets and liabilities recorded at fair value
Impaired real estate available and held for sale	0	0
Impaired land and development	0
Non-recurring basis \| Significant other observable inputs (Level 2)
Assets and liabilities recorded at fair value
Impaired land and development	0
Non-recurring basis \| Significant unobservable inputs (Level 3)
Assets and liabilities recorded at fair value
Impaired real estate	12,400
Impaired real estate available and held for sale	800	6,041
Impaired land and development	21,400
Fair Value \| Recurring basis
Assets and liabilities recorded at fair value
Net Carrying Value	22,842	21,835
Fair Value \| Non-recurring basis
Assets and liabilities recorded at fair value
Impaired real estate	12,400
Impaired real estate available and held for sale	800	$ 6,041
Impaired land and development	$ 21,400
Land and Land Development Asset \| Fair Value \| Non-recurring basis
Assets and liabilities recorded at fair value
Discount rate	6.00%
Estimated sales period	10 years

Fair Value Inputs, Estimated Sales Period

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- Definition

Impaired Land and Development, Fair Value Disclosure

+ References

No definition available.

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- Definition

This element represents impaired OREOs held by the Company as of the end of the reporting period that are valued by the entity at fair value on the balance sheet date.

+ References

No definition available.

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- Definition

Impaired Real Estate Held-for-Sale, Fair Value Disclosure

+ References

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- Definition

Amount of debt 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 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82896770&loc=d3e26610-111562

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 320
-Section 50
-Paragraph 2
-Subparagraph (b)-(g)
-URI http://asc.fasb.org/extlink&oid=75019621&loc=d3e62557-112803

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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.

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- Definition

Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

+ References

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

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