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Derivatives and Hedging Activities - Impact of Fair Value Hedge Accounting on the Carrying Value of the Hedged Items (Details) - Commercial loan fair value hedges $ in Thousands	Mar. 31, 2019 USD ($)
Derivatives, Fair Value [Line Items]
Carrying value of hedged items	$ 95,770
Cumulative gain (loss) fair value hedge adjustment included in carrying amount of hedged items	(94)
Loans receivable
Derivatives, Fair Value [Line Items]
Carrying value of hedged items	95,770
Cumulative gain (loss) fair value hedge adjustment included in carrying amount of hedged items	$ (94)

X

- 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.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Amount of cumulative increase (decrease) in fair value of hedged asset in fair value hedge, attributable to hedged risk.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4EE
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL109999712-113959

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Amount of liability hedged in fair value hedging relationship.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4EE
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL109999712-113959

+ Details

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Balance Type:	credit
Period Type:	instant

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- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

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- Details

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Namespace Prefix:
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Period Type: