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Off-Balance Sheet Arrangements Commitments Guarantees and Contingencies (Narrative) (Detail) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Commitments And Guarantees [Line Items] |  |  |
Credit card guarantees | $ 8,400 | $ 8,300 |
Fully collateralized credit card guarantees | 1,200 | 975 |
Rent expense for operating leases | 30,500 | 28,900 | $ 28,900
Aggregate future minimum rentals to be received under non-cancelable subleases greater than one year | 445 |  |
Partnership Interest of a Director [Member] |  |  |
Commitments And Guarantees [Line Items] |  |  |
Rent expense for operating leases | $ 1,400 | $ 1,000 | $ 963

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- Definition Collateralized Credit Card Guarantees + References No definition available. + Details
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- Definition Commitments And Guarantees [Line Items] + References No definition available. + Details
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- Definition Credit Card Guarantees + References No definition available. + Details
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- Definition Future minimum rental payments in aggregate as of the balance sheet date under operating leases. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=84164653&loc=d3e41551-112718 + Details
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- Definition Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=77902758&loc=d3e41499-112717 + Details
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- Details
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