Investment Securities Investment Securities: Investments with Unrealized Loss Positions (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Sep. 30, 2017	Jun. 30, 2017
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	$ 35,179	$ 28,722
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss	28	77
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Loss	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	35,179	28,722
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss	28	77
U.S. government sponsored enterprise MBS
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	35,179	28,722
Held-to-maturity Securities, Continuous Unrealized Loss Position, Fair Value	35,179	28,722
Held-to-maturity Securities, Continuous Unrealized Loss Position, Accumulated Loss	28	77
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	28	77
Held-to-maturity Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	0	0
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	$ 0	$ 0

Amount of unrealized loss on securities classified as available-for-sale that have been in a loss position for twelve months or longer.

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Amount of unrealized loss on investments in available-for-sale securities that have been in a loss position for less than twelve months.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (a)(2)
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Amount of accumulated unrealized loss on investments in debt securities classified as held-to-maturity that have been in a continuous loss position for twelve months or longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Amount of accumulated unrealized loss on investments in debt securities classified as held-to-maturity in a continuous loss position.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Amount of accumulated unrealized loss on investments in debt securities classified as held-to-maturity that have been in a continuous loss position for less than twelve months.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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