Derivative Financial Instruments - Effect of Cash Flow Hedging on AOCI (Details) - Cash Flow Hedging - Designated as Hedging Instrument - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017
Derivative [Line Items]
Amount of Gain Recognized in OCI on Derivative	$ 1,403
Interest Rate Products
Derivative [Line Items]
Amount of Gain Recognized in OCI on Derivative	1,403
Settled Interest Rate Swaps
Derivative [Line Items]
Amount of Gain Recognized in OCI on Derivative	0
Interest Expense
Derivative [Line Items]
Amount of Loss Reclassified from OCI into Income	369	$ 127
Interest Expense \| Interest Rate Products
Derivative [Line Items]
Amount of Loss Reclassified from OCI into Income	243	0
Interest Expense \| Settled Interest Rate Swaps
Derivative [Line Items]
Amount of Loss Reclassified from OCI into Income	$ 126	$ 127

Amount before tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=114867106&loc=d3e637-108580

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=109978405&loc=d3e80720-113993

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=114867106&loc=SL7669646-108580

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration