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Fair Value Disclosure - Narrative (Details) | 3 Months Ended |
--- | --- | ---
Mar. 31, 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 | $ 2,000,000 |
Gain (loss) on cash flow hedges expected to be reclassified within next twelve months, net of tax | $ 1,500,000 |
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 | 17 | 8
Derivative notional amount | $ 520,800,000.0 | $ 501,900,000.0
Not Designated as Hedging Instrument [Member] | Interest Rate Contract [Member] |  |
Derivative [Line Items] |  |
Derivative liability | $ 13,000,000 |

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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 + Details
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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 + Details
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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 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=109250915&loc=d3e13433-108611 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313 + Details
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