Investment securities HTM contractual maturity table (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013
Amortized cost and fair values of investment securities held to maturity
Securities held to maturity, debt securities due in one year or less, amortized cost	$ 0
Securities held to maturity, debt securities due after one year through five years, amortized cost	0
Securities held to maturity, debt securities due after five years through ten years, amortized cost	15,970
Securities held to maturity, debt securities due after ten years, amortized cost	38,153
Total held to maturity debt securities, amortized Cost	54,123
Securities held to maturity, debt securities due in one year or less, fair value	0
Securities held to maturity, debt securities due in one year through five years, fair value	0
Securities held to maturity, debt securities due after five years through ten years, fair value	15,902
Securities held to maturity, debt securities due after ten years, fair value	37,586
Total held to maturity, debt securities, fair value	$ 53,488

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Amount of held-to-maturity debt securities at fair value maturing in the sixth fiscal year through the tenth fiscal year following the latest fiscal year.

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Amount of held-to-maturity debt securities at fair value maturing in the second fiscal year through the fifth fiscal year following the latest fiscal year.

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