Loans Receivable and Allowance for Loan and Lease Losses Loans Receivable and ALLL Text Tags (Details) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Dec. 31, 2017 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016	Mar. 31, 2017 USD ($)
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Modifications, Recorded Investment	$ 5,700	$ 5,700		$ 6,400
Financing Receivable, Modifications, Number of Contracts	0		0
Financing Receivable, Recorded Investment, Past Due	$ 10,930	10,930		8,098
Other non-performing asset	1,200	1,200
Other Real Estate Owned	$ 1,200	$ 1,200		$ 990
Number of Real Estate Properties	8	8		8
otherrealestateownedresidential	$ 268	$ 268		$ 718
Loans held-for-sale (HFS)	0	$ 0		944
Number of Modified Loan Subsequently Defaulted		0
Loans and Leases Receivable, Related Parties	0	$ 0		4,700
Loans and Leases Receivable, Related Parties, Additions		111
Loans and Leases Receivable, Related Parties, Proceeds		4,800
Nonperforming
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Modifications, Recorded Investment	1,900	1,900		2,500
Performing
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Modifications, Recorded Investment	3,800	$ 3,800		$ 3,900
Financing Receivable, Modifications, Number of Contracts		10		11
Business
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Modifications, Number of Contracts		1
Financing Receivable, Recorded Investment, Past Due	$ 2,233	$ 2,233		$ 1,929

Other non-performing asset

No definition available.

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- Definition

other real estate owned residential

+ References

No definition available.

+ Details

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524

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- Definition

The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=82895541&loc=d3e18845-111554

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953682-111524

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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.

+ Details

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- Definition

Recorded Investment in financing receivables that are past due at the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7A
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953401-111524

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

For an unclassified balance sheet, reflects the carrying amount of unpaid loan amounts due from related parties at the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(e))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

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- Definition

Reflects the amount of new advances made to related parties in the form of loan and lease receivables.

+ References

+ Details

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- Definition

Amount of cash inflow from related parties which reduce the amount of loans and leases receivable due from related parties.

+ References

+ Details

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Balance Type:	debit
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- Definition

The face amount of loans that will be sold to other entities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

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- Definition

The number of real estate properties owned as of the balance sheet date.

+ References

No definition available.

+ Details

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- Definition

Carrying amount as of the balance sheet date of other real estate and foreclosed assets. Other real estate may include real estate investments, real estate loans that qualify as investments in real estate, and premises that are no longer used in operations may also be included in real estate owned. Foreclosed assets include all assets obtained in full or partial satisfaction of a debt arrangement through foreclosure proceedings.

+ References

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- Details

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- Details

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