The amount of expense provided in the period for legal costs incurred on or before the balance sheet date pertaining to resolved, pending or threatened litigation, including arbitration and mediation proceedings.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.3)
-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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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

Amount of damages awarded to the plaintiff in the legal matter.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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-Publisher FASB
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-Section 50
-Paragraph 9
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14557-108349

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- Definition

The estimated maximum amount of possible loss from the contingency.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)
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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
-Section 50
-Paragraph 9
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-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14557-108349

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- Definition

The estimated minimum amount of possible loss from the contingency.

+ References

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Contingent Liabilities (Narrative) (Details) - USD ($)		12 Months Ended
Contingent Liabilities (Narrative) (Details) - USD ($)	Jan. 17, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Loss Contingencies [Line Items]
Legal fees		$ 21,000,000	$ 24,000,000	$ 24,000,000
Pending Litigation
Loss Contingencies [Line Items]
Minimum amount of reasonably possible losses		0
Estimated maximum amount of reasonably possible losses		$ 33,000,000
Butte Local Development v. Masters Group v. Comerica Bank
Loss Contingencies [Line Items]
Amount of damages awarded by the jury	$ 52,000,000