Core Deposit Intangibles in Amounts of One Hundred Thousand or more, by Remaining Term to Maturity (Detail) $ in Thousands	Dec. 31, 2018 USD ($)
Debt Instrument [Line Items]
CDs of $100,000 or More Maturing Within, 3 Months or Less	$ 1,664,185
CDs of $100,000 or More Maturing Within, Over 3 to 6 Months	1,776,418
CDs of $100,000 or More Maturing Within, Over 6 to 12 Months	2,324,535
CDs of $100,000 or More Maturing Within, Over 12 Months	1,232,625
CDs of $100,000 or More Maturing Within, Total	$ 6,997,763

- Definition

Amount of time deposit liabilities, including certificates of deposit, in denominations of $100,000 or more, maturing after twelve months from the balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher SEC
-Name Industry Guide
-Number 3
-Section V
-Paragraph D-E

+ Details

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- Definition

Amount of time deposit liabilities, including certificates of deposit, in denominations of $100,000 or more, maturing within six to twelve months after the balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher SEC
-Name Industry Guide
-Number 3
-Section V
-Paragraph D-E

+ Details

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- Definition

Amount of time deposit liabilities, including certificates of deposit, in denominations of $100,000 or more, maturing within three months or fewer from the balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher SEC
-Name Industry Guide
-Number 3
-Section V
-Paragraph D-E

+ Details

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Namespace Prefix:	us-gaap_
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- Definition

Amount of time deposit liabilities, including certificates of deposit, in denominations of $100,000 or more, maturing within three to six months after the balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher SEC
-Name Industry Guide
-Number 3
-Section V
-Paragraph D-E

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of time deposit liabilities, including certificates of deposit, in denominations of $100,000 or more.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher SEC
-Name Industry Guide
-Number 3
-Section V
-Paragraph D-E

+ Details

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Namespace Prefix:	us-gaap_
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