Derivatives Pre-Tax Gains (Losses) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized gain (loss) on interest rate cash flow hedges, pre-tax, accumulated other comprehensive income (loss)	$ (2,441)	$ 1,545
Designated as Hedging Instrument [Member] \| Interest Rate Swap [Member] \| Cash Flow Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized gain (loss) on interest rate cash flow hedges, pre-tax, accumulated other comprehensive income (loss)	(2,441)	1,545
Designated as Hedging Instrument [Member] \| Interest Rate Swap [Member] \| Interest Expense [Member] \| Cash Flow Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Cash flow hedge gain (loss) reclassified to interest expense, net	$ 114	$ 60

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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