Investment Securities Investment Securities-Schedule of Unealized Loss (Details) - USD ($) $ in Thousands		Sep. 30, 2017	Mar. 31, 2017
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss		$ 120	$ 1,403
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value		11,283	47,162
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss		1,312	537
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value		44,811	11,446
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss		1,432	1,940
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value		56,094	58,608
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss		3	60
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value		2,323	7,623
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss		19	0
Held-to-maturity Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value		1,820	0
Held-to-maturity Securities, Continuous Unrealized Loss Position, Accumulated Loss		22	60
Held-to-maturity Securities, Continuous Unrealized Loss Position, Fair Value		4,143	7,623
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		69	1,171
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value		7,458	34,716
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss		766	41
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value		27,186	1,942
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss		835	1,212
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value		34,644	36,658
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		51	92
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value		3,825	7,482
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss		34	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value		3,045	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss		85	92
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value		6,870	7,482
Corporate Bonds
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss		0	140
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value		0	4,964
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss		79	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value		5,013	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss		79	140
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value		5,013	4,964
Other investments
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]	433	496
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	[1]	9,567	9,504
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	[1]	433	496
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	[1]	9,567	9,504
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		3	60
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value		2,323	7,623
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss		19	0
Held-to-maturity Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value		1,820	0
Held-to-maturity Securities, Continuous Unrealized Loss Position, Accumulated Loss		22	60
Held-to-maturity Securities, Continuous Unrealized Loss Position, Fair Value		$ 4,143	$ 7,623

[1] (1) Primarily comprised of an investment in a CRA fund with 95% of its underlying investments consisting of government and agency-backed securities.