End date of current fiscal year in the format --MM-DD.

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- Definition

This is focus fiscal year of the document report in CCYY format. For a 2006 annual report, which may also provide financial information from prior periods, fiscal 2006 should be given as the fiscal year focus. Example: 2006.

+ References

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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

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- Definition

Derivative, Early Termination Date

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No definition available.

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
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-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
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-Topic 835
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-Section 45
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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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- Definition

Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4D
-Subparagraph (c)(2)
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-Name Accounting Standards Codification
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-SubTopic 20
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- Definition

Fixed interest rate related to the interest rate derivative.

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

Date the derivative contract matures, in CCYY-MM-DD format.

+ References

No definition available.

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- Definition

Reference to the index or unit of measurement for the underlying which establishes the pricing terms of the derivative instrument. For example, the basis on the underlying for a natural gas futures contract might be the NYMEX price per million British thermal units (MMBtu).

+ References

No definition available.

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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

Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-04.(a))
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-SubTopic 10
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-Paragraph 1
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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Derivative Financial Instruments - Fair Value of Derivatives (Details) - USD ($)	12 Months Ended
	Dec. 31, 2015	Aug. 01, 2015	Dec. 31, 2014
Derivatives, Fair Value [Line Items]
Document Fiscal Year Focus	2015
Current Fiscal Year End Date	--12-31
Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months	$ 47,609,000
Long-term Debt, Maturities, Repayments of Principal in Year Two	423,076,000
Long-term Debt, Maturities, Repayments of Principal in Year Three	62,461,000
Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	$ 220,000,000
Derivative @ 2.479% 75K [Member]
Derivatives, Fair Value [Line Items]
Derivative, Inception Date	Aug. 01, 2015
Derivative, Maturity Date	Aug. 01, 2025
Derivative, Early Termination Date	Feb. 01, 2016
Derivative, Notional Amount	$ 75,000,000
Derivative, Underlying Basis	3 Month LIBOR
Derivative, Fixed Interest Rate	2.479%
Derivative Liability, Fair Value, Gross Liability	$ 0		$ (289,000)
Derivative A @ 2.479% 50K [Member]
Derivatives, Fair Value [Line Items]
Derivative, Inception Date	Aug. 01, 2015
Derivative, Maturity Date	Aug. 01, 2025
Derivative, Early Termination Date	Feb. 01, 2016
Derivative, Notional Amount	$ 50,000,000
Derivative, Underlying Basis	3 Month LIBOR
Derivative, Fixed Interest Rate	2.479%
Derivative Liability, Fair Value, Gross Liability	$ 0		(193,000)
Derivative B @ 2.479% 50K [Member]
Derivatives, Fair Value [Line Items]
Derivative, Inception Date	Aug. 01, 2015
Derivative, Maturity Date	Aug. 01, 2025
Derivative, Early Termination Date	Feb. 01, 2016
Derivative, Notional Amount	$ 50,000,000
Derivative, Underlying Basis	3 Month LIBOR
Derivative, Fixed Interest Rate	2.479%
Derivative Liability, Fair Value, Gross Liability	$ 0		(193,000)
Derivative @ 2.196% 28.1K [Member]
Derivatives, Fair Value [Line Items]
Derivative, Inception Date	Oct. 16, 2013
Derivative, Maturity Date	Oct. 16, 2020
Derivative, Notional Amount	$ 28,100,000
Derivative, Underlying Basis	1 Month LIBOR
Derivative, Fixed Interest Rate	2.196%
Derivative Liability, Fair Value, Gross Liability	$ (898,000)		(764,000)
Derivative @ 3.41% 45K [Member] [Member]
Derivatives, Fair Value [Line Items]
Derivative, Inception Date	Aug. 01, 2015
Derivative, Maturity Date	Aug. 01, 2025
Derivative, Early Termination Date	Feb. 01, 2016
Derivative, Notional Amount	$ 45,000,000
Derivative, Underlying Basis	3 Month LIBOR
Derivative, Fixed Interest Rate	3.4115%
Derivative Liability, Fair Value, Gross Liability	$ 0		(3,964,000)
Derivative @ 3.488% 20K [Member]
Derivatives, Fair Value [Line Items]
Derivative, Inception Date	Jun. 15, 2017
Derivative, Maturity Date	Jun. 15, 2027
Derivative, Early Termination Date	Dec. 15, 2017
Derivative, Notional Amount	$ 20,000,000
Derivative, Underlying Basis	3 Month LIBOR
Derivative, Fixed Interest Rate	3.4875%
Derivative Liability, Fair Value, Gross Liability	$ (1,798,000)		(1,227,000)
Derivative @ 3.48% 100K [Member]
Derivatives, Fair Value [Line Items]
Derivative, Inception Date	Jun. 15, 2017
Derivative, Maturity Date	Jun. 15, 2027
Derivative, Early Termination Date	Dec. 15, 2017
Derivative, Notional Amount	$ 100,000,000
Derivative, Underlying Basis	3 Month LIBOR
Derivative, Fixed Interest Rate	3.48%
Derivative Liability, Fair Value, Gross Liability	$ (8,922,000)		(6,080,000)
Derivative @ 3.48% 100K 2 [Member]
Derivatives, Fair Value [Line Items]
Derivative, Inception Date	Jun. 15, 2017
Derivative, Maturity Date	Jun. 15, 2027
Derivative, Early Termination Date	Dec. 15, 2017
Derivative, Notional Amount	$ 100,000,000
Derivative, Underlying Basis	3 Month LIBOR
Derivative, Fixed Interest Rate	3.48%
Derivative Liability, Fair Value, Gross Liability	$ (8,921,000)		(6,084,000)
Unsecured Maturities [Member]
Derivatives, Fair Value [Line Items]
Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months	0
Long-term Debt, Maturities, Repayments of Principal in Year Two	300,000,000
Long-term Debt, Maturities, Repayments of Principal in Year Three	0
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Measurements, Recurring [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	$ (20,539,000)		$ (18,794,000)
Unsecured Debt [Member]
Derivatives, Fair Value [Line Items]
Debt Instrument, Interest Rate, Effective Percentage	3.696%
3.90% unsecured maturing 11/1/2025 [Member] \| Unsecured Debt [Member]
Derivatives, Fair Value [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		3.90%
Debt Instrument, Face Amount		$ 250,000,000