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

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

The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=35736893&loc=d3e80748-113994

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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.

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No definition available.

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- Definition

The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Paragraph 4D
-Subparagraph (b)
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- Definition

The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

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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.

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

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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

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- Definition

Amount of the cost of borrowed funds accounted for as interest expense.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6450988&loc=d3e26243-108391

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.9)
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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Fair value as of the balance sheet date of all interest rate derivative assets designated as cash flow hedging instruments.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
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Fair value as of the balance sheet date of all interest rate derivatives designated as cash flow hedging instruments.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 5
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Fair value as of the balance sheet date of all interest rate derivative liabilities designated as cash flow hedging instruments.

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Derivatives (Details) - USD ($) $ in Thousands	3 Months Ended
Derivatives (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Derivative [Line Items]
Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income (Loss), Effective Portion, Net	$ 9,505	$ (68)
Amount reclassified from accumulated other comprehensive loss	2,138	(2,654)
Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months	$ 4,400
Derivative @ 2.36600% 37.5K [Member] [Domain]
Derivative [Line Items]
Derivative, Inception Date	Jun. 02, 2017
Derivative, Maturity Date	Jun. 02, 2027
Derivative, Notional Amount	$ 37,500
Derivative, Description of Variable Rate Basis	1 Month LIBOR with Floor
Derivative, Fixed Interest Rate	2.366%
Interest Rate Cash Flow Hedge Asset at Fair Value	$ (879)
Interest Rate Cash Flow Hedge Liability at Fair Value			$ 177
Derivative $33M Swap [Member]
Derivative [Line Items]
Derivative, Inception Date	Dec. 01, 2016
Derivative, Maturity Date	Nov. 01, 2023
Derivative, Notional Amount	$ 33,000
Derivative, Description of Variable Rate Basis	1 Month LIBOR
Derivative, Fixed Interest Rate	1.49%
Interest Rate Cash Flow Hedge Asset at Fair Value	$ (1,779)		(1,166)
Derivatives 200K @ 1.04770% and 65K @ 1.07000% [Member] [Domain]
Derivative [Line Items]
Derivative, Inception Date	Aug. 01, 2016
Derivative, Maturity Date	Jan. 05, 2022
Derivative, Notional Amount	$ 265,000
Derivative, Description of Variable Rate Basis	1 Month LIBOR with Floor
Derivative, Fixed Interest Rate	1.053%
Interest Rate Cash Flow Hedge Asset at Fair Value	$ (13,969)		(10,744)
Derivative $300M Term [Member]
Derivative [Line Items]
Derivative, Inception Date	Apr. 03, 2017
Derivative, Maturity Date	Dec. 02, 2020
Derivative, Notional Amount	$ 300,000
Derivative, Fixed Interest Rate	1.824%
Interest Rate Cash Flow Hedge Asset at Fair Value	$ (4,690)		(1,804)
Swap [Member]
Derivative [Line Items]
Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months	$ 8,400
Derivative @ 1.30250% 20.0M [Member]
Derivative [Line Items]
Derivative, Inception Date	Apr. 07, 2016
Derivative, Maturity Date	Apr. 01, 2023
Derivative, Notional Amount	$ 20,000
Derivative, Description of Variable Rate Basis	1 Month LIBOR
Derivative, Fixed Interest Rate	1.3025%
Interest Rate Cash Flow Hedge Asset at Fair Value	$ (1,130)		(801)
Fair Value, Measurements, Recurring [Member]
Derivative [Line Items]
Interest Rate Cash Flow Hedge Asset at Fair Value	(22,447)		(14,515)
Interest Rate Cash Flow Hedge Liability at Fair Value			177
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Measurements, Recurring [Member]
Derivative [Line Items]
Interest Rate Cash Flow Hedge Asset at Fair Value	(22,447)		(14,515)
Interest Rate Cash Flow Hedge Liability at Fair Value			177
Interest Rate Cash Flow Hedge Derivative at Fair Value, Net	22,447		$ 14,338
Parent Company [Member]
Derivative [Line Items]
Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income (Loss), Effective Portion, Net	9,505	(68)
Interest Expense	$ 36,785	$ 27,199