Loans - Concentrations and Restrictions (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Dec. 31, 2018
Consumer \| Residential Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration risk, percentage	23.00%
Consumer \| Consumer Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration risk, percentage	22.00%
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loans	$ 21,123,055	$ 20,545,198
Commercial \| Finance And Insurance Companies
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loans	$ 2,600,000
Percentage of commercial & industrial loan portfolio	15.00%
Percentage contributed in total loan	9.00%
Commercial \| Loans To Mortgage Companies
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loans	$ 2,300,000
Percentage of commercial & industrial loan portfolio	13.00%
Percentage contributed in total loan	8.00%
Commercial \| Finance Insurance And Loans To Mortgage Companies
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of commercial & industrial loan portfolio	28.00%

Bank-related and TRUPs loans divided by total loan portfolio.

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- Definition

Percentage of Commercial And Industrial Loan Portfolio

+ References

No definition available.

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No definition available.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

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Amount, before allowance and fees, of loans and leases receivable. Excludes loans and leases covered under loss sharing agreements.

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