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Commitments and Contingencies (Narrative) (Detail) $ in Millions | Sep. 30, 2018 USD ($) Lawsuits
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Commitments and Contingencies [Abstract] |
Other material lawsuits pending | Lawsuits | 0
Operating leases future minimum payments due | $ | $ 34
Pledged Sales Tax Base Amount [Member] |
Loss Contingencies [Line Items] |
COFINA and PR Commonwealth settlement percentage | 53.65%
Cash Held In Trust BONY Mellon [Member] |
Loss Contingencies [Line Items] |
COFINA and PR Commonwealth settlement percentage | 100.00%

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- Definition Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 10 -Section 55 -Paragraph 40 -Subparagraph (Note 3) -URI http://asc.fasb.org/extlink&oid=82846649&loc=d3e38371-112697 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=77902758&loc=d3e41502-112717 + Details
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