Mortgage-backed Securities: Schedule of mortgage-backed securities held to maturity (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013		Mar. 31, 2013
FHLMC mortgage-backed securities
Held-to-maturity Securities, Amortized Cost before Other than Temporary Impairment	$ 29	[1]	$ 31
Held-to-maturity Securities, Unrecognized Holding Gain	2	[1]	3
Held-to-maturity Securities, Fair Value	31	[1]	34
FNMA mortgage-backed securities
Held-to-maturity Securities, Amortized Cost before Other than Temporary Impairment	79	[2]	94
Held-to-maturity Securities, Unrecognized Holding Gain			1
Held-to-maturity Securities, Fair Value	79	[2]	95
Mortgage-backed
Held-to-maturity Securities, Amortized Cost before Other than Temporary Impairment	108		125
Held-to-maturity Securities, Unrecognized Holding Gain	2		4
Held-to-maturity Securities, Fair Value	$ 110		$ 129

[1] Federal Home Loan Mortgage Corporation (FHLMC)

[2] Federal National Mortgage Association (FNMA)