Fair Value Disclosure - Narrative (Details)	6 Months Ended
Jun. 30, 2019 USD ($) Instrument	Dec. 31, 2018 USD ($) Instrument
Derivative [Line Items]
Gain (loss) on cash flow hedges expected to be reclassified within next twelve months	$ 1,900,000
Gain (loss) on cash flow hedges expected to be reclassified within next twelve months, net of tax	$ 1,400,000
Designated as Hedging Instrument [Member] \| Fair Value Hedging [Member] \| Interest Rate Contract [Member]
Derivative [Line Items]
Number of derivative instruments \| Instrument	8	9
Derivative notional amount	$ 450,000,000.0	$ 500,000,000.0
Designated as Hedging Instrument [Member] \| Cash Flow Hedging [Member] \| Interest Rate Contract [Member]
Derivative [Line Items]
Number of derivative instruments \| Instrument	14	8
Derivative notional amount	$ 470,000,000.0	$ 501,900,000
Not Designated as Hedging Instrument [Member] \| Interest Rate Contract [Member]
Derivative [Line Items]
Derivative liability	$ 10,200,000

Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months, Gross

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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

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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=112277219&loc=d3e80748-113994

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- Definition

Fair value, after the 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 not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
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-Section 55
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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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- Definition

The number of derivative instruments of a particular group held by the entity.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
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