Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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- Definition

Amount of assets pledged to secure a debt instrument.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (d)
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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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The aggregate fair value amounts of derivative instruments that contain credit-risk-related contingent features that are in a net liability position at the end of the reporting period. For nonderivative instruments that are designated and qualify as hedging instruments, the fair value amounts are the carrying value of the nonderivative hedging instrument, including the adjustment for the foreign currency transaction gain (loss) on that instrument.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4H
-Subparagraph (c)
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- Definition

The number of derivative instruments of a particular group held by the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
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-Section 50
-Paragraph 1A
-Subparagraph (d)
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- Definition

The increase (decrease) during the reporting period in interest payable, which represents the amount owed to note holders, bond holders, and other parties for interest earned on loans or credit extended to the reporting entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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Represents the total of interest and dividend income, including any amortization and accretion (as applicable) of discounts and premiums, earned from (1) loans and leases whether held-for-sale or held-in-portfolio; (2) investment securities; (3) federal funds sold; (4) securities purchased under agreements to resell; (5) investments in banker's acceptances, commercial paper, or certificates of deposit; (6) dividend income; or (7) other investments not otherwise specified herein.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.1-5)
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Derivatives and Hedging Activities - Additional Information (Detail)	3 Months Ended		6 Months Ended		12 Months Ended
	Mar. 31, 2018 USD ($) Contract	Mar. 31, 2017 USD ($)	Mar. 31, 2018 USD ($) Contract	Mar. 31, 2017 USD ($)	Mar. 31, 2019 USD ($)
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Interest income	$ 15,847,000	$ 14,379,000	$ 31,223,000	$ 29,029,000
Increase (decrease) in accrued interest payable			34,000	$ (183,000)
Net liability position of derivatives	0		0
Debt Instrument, collateral amount	0		0
Designated as Hedging Instrument [Member] \| Cash Flow Hedges of Interest Rate Risk [Member] \| Reclassification Out of Accumulated Other Comprehensive Income (Loss) [Member]
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Interest income	$ 76,000		$ 99,000
Designated as Hedging Instrument [Member] \| Cash Flow Hedges of Interest Rate Risk [Member] \| Scenario, Forecast [Member] \| Reclassification Out of Accumulated Other Comprehensive Income (Loss) [Member]
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Increase (decrease) in accrued interest payable					$ 0
Designated as Hedging Instrument [Member] \| Cash Flow Hedges of Interest Rate Risk [Member] \| Interest Rate Swaps [Member] \| Variable Rate [Member] \| FHLB Advances [Member]
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Derivative, number of instruments \| Contract	3		3
Derivative, notional principal amount	$ 75,000,000		$ 75,000,000