Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=115931803&loc=d3e12069-110248

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- Definition

Fair value portion of guarantee, including, but not limited to, financial standby letter of credit, fair value guarantee, guarantee of collection of scheduled contractual cash flows from financial assets, and contracts that contingently require the guarantor to make payments or perform services.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=115931803&loc=d3e12201-110248

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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.

+ References

No definition available.

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- Definition

Number of plaintiffs that have filed claims pertaining to a loss contingency.

+ References

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Commitments and Contingent Liabilities (Narrative) (Details) $ in Thousands	Aug. 23, 2017 plaintiff	Apr. 24, 2017 plaintiff	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Loss Contingencies [Line Items]
Guarantee maximum exposure			$ 705,478
Equipment lease obligations assumed by third party
Loss Contingencies [Line Items]
Guarantee maximum exposure			28,000	$ 35,000
Guarantees at fair value			$ 734	$ 1,040
Fitzwater Litigation \| Pending litigation
Loss Contingencies [Line Items]
Number of plaintiffs \| plaintiff		3
Casey Litigation \| Pending litigation
Loss Contingencies [Line Items]
Number of plaintiffs \| plaintiff	2