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Borrowings - Summary of Information Pertaining to Borrowings (Detail) - USD ($) $ in Thousands | Sep. 30, 2016 | Dec. 31, 2015
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Long Term And Short Term Debt [Line Items] |  |
Short-term borrowings | $ 605,949 | $ 418,086
Long-term borrowings | 60,922 | 162,662
Total Borrowings | $ 666,871 | $ 580,748
Short-term borrowings, Weighted Average Rate | 0.56% | 0.44%
Long-term borrowings, Weighted Average Rate | 3.06% | 1.39%
Total Borrowings, Weighted Average Rate | 0.79% | 0.71%
Securities Sold under Repurchase Agreements |  |
Long Term And Short Term Debt [Line Items] |  |
Short-term borrowings | $ 40,949 | $ 62,086
Short-term borrowings, Weighted Average Rate | 0.01% | 0.01%
Short-Term Borrowings |  |
Long Term And Short Term Debt [Line Items] |  |
Short-term borrowings | $ 565,000 | $ 356,000
Short-term borrowings, Weighted Average Rate | 0.60% | 0.52%
Other Long-Term Borrowings |  |
Long Term And Short Term Debt [Line Items] |  |
Long-term borrowings | $ 15,303 | $ 117,043
Long-term borrowings, Weighted Average Rate | 2.91% | 0.81%
Junior Subordinated Debt Securities |  |
Long Term And Short Term Debt [Line Items] |  |
Long-term borrowings | $ 45,619 | $ 45,619
Long-term borrowings, Weighted Average Rate | 3.11% | 2.89%

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- Definition Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(16)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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