Derivative Financial Instruments (Summary of Interest Rate Swaps) (Details)	12 Months Ended
Dec. 31, 2018 USD ($)
November 2016 to March 2021 [Member]
Derivative [Line Items]
Trade Date	Nov. 13, 2016
Notional Amount	$ 200,000,000
Coverage Period	November 2016 to March 2021
Risk Coverage	USD-LIBOR
April 2016 to March 2023 [Member]
Derivative [Line Items]
Trade Date	Apr. 01, 2016
Notional Amount	$ 100,000,000
Coverage Period	April 2016 to March 2023
Risk Coverage	USD-LIBOR
November 2018 to November 2023 [Member]
Derivative [Line Items]
Trade Date	Nov. 28, 2018
Notional Amount	$ 200,000,000
Coverage Period	November 2018 to November 2023
Risk Coverage	USD-LIBOR
March 2021 to March 2025 [Member]
Derivative [Line Items]
Trade Date	Nov. 28, 2018
Notional Amount	$ 100,000,000
Coverage Period	March 2021 to March 2025
Risk Coverage	USD-LIBOR

Derivative maturity coverage.

No definition available.

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- Definition

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

+ Details

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Period Type:	instant

- Definition

Date the entity entered into the derivative contract, in CCYY-MM-DD format.

+ References

No definition available.

+ Details

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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.

+ Details

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- Definition

Description of primary underlying risk exposure associated with the derivative, for example, but not limited to, interest rate risk, credit risk, foreign exchange rate risk, or price risk.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5580258-113959

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=109980867&loc=d3e41641-113959

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579240-113959

+ Details

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- Details

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- Details

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- Details

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- Details

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