Loans and Leases - Minimum Future Lease Payments to be Received from Lease Financings (Detail) $ in Thousands	Dec. 31, 2017 USD ($)
Receivables [Abstract]
2018	$ 310,207
2019	297,599
2020	208,613
2021	150,553
2022	96,871
Later years	183,562
Total	$ 1,247,405

Amount of minimum lease payments to be received by the lessor for capital leases.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84165051&loc=d3e45377-112738

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- Definition

Amount of minimum lease payments to be received by the lessor for capital leases in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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- Definition

Amount of minimum lease payments to be received by the lessor for capital leases after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of minimum lease payments to be received by the lessor for capital leases in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of minimum lease payments to be received by the lessor for capital leases in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of minimum lease payments to be received by the lessor for capital leases in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of minimum lease payments to be received by the lessor for capital leases in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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