Accumulated other comprehensive income loss transfers from available for sale securities to held to maturity.

No definition available.

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- Definition

Available For Sale And Held To Maturity Securities Amount Callable Amortized Cost

+ References

No definition available.

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- Definition

Available For Sale And Held To Maturity Securities Amount Callable Fair Value Disclosure

+ References

No definition available.

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- Definition

Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value

+ References

No definition available.

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- Definition

Securities Transferred From Available For Sale To Held To Maturity

+ References

No definition available.

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- Definition

Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27337-111563

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- Definition

Amount of realized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27357-111563

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- Definition

Amount of realized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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- Definition

The fair value, as of the date of each statement of financial position presented, of securities that are restricted as collateral for the payment of other debt obligations, and that are reclassified and separately reported in the statement of financial position because the transferee has the right by contract or custom to sell or re-pledge them.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=66007379&loc=d3e113888-111728

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- Definition

The fair value, as of the date of each statement of financial position presented, of securities which are owned but transferred to serve as collateral for the payment of repurchase agreements, and that are reclassified and separately reported in the statement of financial position because the transferee has the right by contract or custom to sell or re-pledge them.

+ References

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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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Securities - Additional Information (Detail) - USD ($)	3 Months Ended			9 Months Ended
Securities - Additional Information (Detail) - USD ($)	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2013	Sep. 30, 2018	Dec. 31, 2017
Debt Securities, Available-for-sale [Line Items]
Available-for-sale securities transferred to held-to-maturity securities			$ 536,000,000
Unrealized net loss on securities transferred from available-for-sale to held-to-maturity, Gross			$ 13,300,000
Realized gains on the sale of available-for-sale securities	$ 0	$ 0		$ 248,000
Realized losses on sale of available-for-sale securities	0			0
Corporate debt securities, callable, amortized cost	53,800,000			53,800,000
Corporate debt securities, callable, estimated fair value	51,800,000			51,800,000
Securities pledged for other debt obligations, at fair value	578,500,000			578,500,000	$ 466,400,000
Reverse Repurchase Agreement
Debt Securities, Available-for-sale [Line Items]
Securities pledged for repurchase agreements, at fair value	$ 76,800,000			$ 76,800,000	58,000,000
Investment Securities \| U.S. Agency Obligations
Debt Securities, Available-for-sale [Line Items]
Available-for-sale securities, continuous unrealized loss position, 12 months or longer, accumulated loss					0
Available-for-sale securities, continuous unrealized loss position, 12 months or longer, fair value					$ 0