Investment Securities Investment Securities Unrealized losses and fair value of securities (Details) - USD ($) $ in Thousands		9 Months Ended	12 Months Ended
		Dec. 31, 2016	Mar. 31, 2016
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss		$ 138
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value		10,661
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss		0
Held-to-maturity Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value		0
Held-to-maturity Securities, Continuous Unrealized Loss Position, Accumulated Loss		138
Held-to-maturity Securities, Continuous Unrealized Loss Position, Fair Value		10,661
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss		1,550	$ 3
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value		48,165	2,996
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss		551	375
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value		11,453	36,537
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss		2,101	378
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value		59,618	39,533
Securities Continuous Loss Position Less than 12 months		1,688
Securities Continuous Unrealized Loss Position Less than 12 months Fair Value		58,826
Securities, Continuous Unrealized Loss Position ,12 months or Longer		551
Securities, Continuous Unrealized Loss Position, 12 months or Longer, Fair Value		11,453
Unrealized Loss on Securities		2,239	378
Securities, Continuous Unrealized Loss Position, fair value		70,279
Mortgage-backed securities
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss		1,240	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value		35,517	0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss		55	136
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value		1,949	15,502
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss		1,295	136
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value		37,466	15,502
US Government Agency Securities
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss		125	3
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value		7,723	2,996
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss		0	32
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value		0	11,242
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss		125	35
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value		7,723	14,238
Corporate Bond Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss		185
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value		4,925
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss		0
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value		0
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss		185
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value		4,925
Other
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	[1]	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	[1]	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	[1]	496	207
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	[1]	9,504	9,793
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	[1]	496	207
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	[1]	9,504	$ 9,793
Mortgage-backed securities
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss		138
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value		10,661
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss		0
Held-to-maturity Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value		0
Held-to-maturity Securities, Continuous Unrealized Loss Position, Accumulated Loss		138
Held-to-maturity Securities, Continuous Unrealized Loss Position, Fair Value		$ 10,661

[1] (1) CRA fund comprised of over 95% agency securities.