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Activity in Allowance for Losses for Non-Covered Loans and Covered Loans (Detail) - USD ($) $ in Thousands | Dec. 31, 2017 | Dec. 31, 2016
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Financing Receivable, Allowance for Credit Losses [Line Items] |  |
Allowance for Loan Losses, Individually evaluated for impairment |  | $ 577
Allowance for Loan Losses, Collectively evaluated for impairment | $ 158,046 | 155,947
Allowance for Loan Losses |  | 181,991
Acquired loans with deteriorated credit quality |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |
Allowance for Loan Losses, other |  | 25,467
Mortgage Receivable |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |
Allowance for Loan Losses, Collectively evaluated for impairment | 128,275 | 123,925
Allowance for Loan Losses |  | 135,909
Mortgage Receivable | Acquired loans with deteriorated credit quality |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |
Allowance for Loan Losses, other |  | 11,984
Other loans |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |
Allowance for Loan Losses, Individually evaluated for impairment |  | 577
Allowance for Loan Losses, Collectively evaluated for impairment | $ 29,771 | 32,022
Allowance for Loan Losses |  | 46,082
Other loans | Acquired loans with deteriorated credit quality |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |
Allowance for Loan Losses, other |  | $ 13,483

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- Definition Financing Receivable, Allowance For Credit Losses, Allocated + References No definition available. + Details
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- Definition A valuation allowance for financing receivables that are expected to be uncollectible. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524 + Details
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- Definition The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524 + Details
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- Definition Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524 + Details
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