Investments (Details 3) - USD ($) $ in Thousands	Jun. 30, 2018	Mar. 31, 2018
Contractual Maturity of Investment Securities
Due in less than one year, Amortized Cost	$ 1,125
Due after one year through five years, Amortized Cost	3,020
Due after five years through ten years, Amortized Cost	930
Due after ten years, Amortized Cost	3,339
Debt Securities without Single Maturity Date, Amortized Cost	7,334
Debt Securities, Amortized Cost Basis	15,748	$ 16,412
Due in less than one year, Fair Value	1,108
Due after one year through five years, Fair Value	2,934
Due after five years through ten years, Fair Value	908
Due after ten years, Fair Value	3,421
Debt Securities without Single Maturity Date, Fair Value	7,152
Debt Securities, Available-for-sale	$ 15,523	$ 16,181

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

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+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27198-111563

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Amount of 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 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109979856&loc=d3e26610-111562

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

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