Certain Financial Statement Information Fair Value (Details) (USD $) | Sep. 30, 2014 | Mar. 31, 2014 |
In Thousands, unless otherwise specified |
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis | ' | | ' | |
Available-for-sale securities measured at fair value on a recurring basis | $89,518 | | $106,583 | |
Cash, cash equivalents and available-for-sale investments measured at fair value on recurring basis | 89,518 | | 106,583 | |
Level 1 [Member] | ' | | ' | |
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis | ' | | ' | |
Cash, cash equivalents and available-for-sale investments measured at fair value on recurring basis | 73,470 | | 90,740 | |
Level 2 [Member] | ' | | ' | |
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis | ' | | ' | |
Cash, cash equivalents and available-for-sale investments measured at fair value on recurring basis | 16,048 | | 15,843 | |
Level 3 [Member] | ' | | ' | |
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis | ' | | ' | |
Cash, cash equivalents and available-for-sale investments measured at fair value on recurring basis | 0 | | 0 | |
Cash [Member] | ' | | ' | |
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis | ' | | ' | |
Cash and cash equivalents measured at fair value on a recurring basis | 47,709 | | 65,867 | |
Cash [Member] | Level 1 [Member] | ' | | ' | |
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis | ' | | ' | |
Cash and cash equivalents measured at fair value on a recurring basis | 47,709 | | 65,867 | |
Cash [Member] | Level 2 [Member] | ' | | ' | |
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis | ' | | ' | |
Cash and cash equivalents measured at fair value on a recurring basis | 0 | | 0 | |
Cash [Member] | Level 3 [Member] | ' | | ' | |
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis | ' | | ' | |
Cash and cash equivalents measured at fair value on a recurring basis | 0 | | 0 | |
Cash equivalents [Member] | ' | | ' | |
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis | ' | | ' | |
Cash and cash equivalents measured at fair value on a recurring basis | 6,237 | | 5,672 | |
Cash equivalents [Member] | Level 1 [Member] | ' | | ' | |
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis | ' | | ' | |
Cash and cash equivalents measured at fair value on a recurring basis | 6,237 | | 5,672 | |
Cash equivalents [Member] | Level 2 [Member] | ' | | ' | |
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis | ' | | ' | |
Cash and cash equivalents measured at fair value on a recurring basis | 0 | | 0 | |
Cash equivalents [Member] | Level 3 [Member] | ' | | ' | |
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis | ' | | ' | |
Cash and cash equivalents measured at fair value on a recurring basis | 0 | | 0 | |
U.S Treasury securities and agency bonds [Member] | ' | | ' | |
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis | ' | | ' | |
Available-for-sale securities measured at fair value on a recurring basis | 2,842 | | 2,838 | |
U.S Treasury securities and agency bonds [Member] | Level 1 [Member] | ' | | ' | |
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis | ' | | ' | |
Available-for-sale securities measured at fair value on a recurring basis | 2,842 | | 2,838 | |
U.S Treasury securities and agency bonds [Member] | Level 2 [Member] | ' | | ' | |
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis | ' | | ' | |
Available-for-sale securities measured at fair value on a recurring basis | 0 | | 0 | |
U.S Treasury securities and agency bonds [Member] | Level 3 [Member] | ' | | ' | |
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis | ' | | ' | |
Available-for-sale securities measured at fair value on a recurring basis | 0 | | 0 | |
Corporate bonds [Member] | ' | | ' | |
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis | ' | | ' | |
Available-for-sale securities measured at fair value on a recurring basis | 10,901 | | 10,627 | |
Corporate bonds [Member] | Level 1 [Member] | ' | | ' | |
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis | ' | | ' | |
Available-for-sale securities measured at fair value on a recurring basis | 0 | | 0 | |
Corporate bonds [Member] | Level 2 [Member] | ' | | ' | |
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis | ' | | ' | |
Available-for-sale securities measured at fair value on a recurring basis | 10,901 | | 10,627 | |
Corporate bonds [Member] | Level 3 [Member] | ' | | ' | |
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis | ' | | ' | |
Available-for-sale securities measured at fair value on a recurring basis | 0 | | 0 | |
Mortgage-backed and asset-backed securities [Member] | ' | | ' | |
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis | ' | | ' | |
Available-for-sale securities measured at fair value on a recurring basis | 1,960 | [1] | 2,074 | [1] |
Mortgage-backed and asset-backed securities [Member] | Level 1 [Member] | ' | | ' | |
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis | ' | | ' | |
Available-for-sale securities measured at fair value on a recurring basis | 0 | | 0 | |
Mortgage-backed and asset-backed securities [Member] | Level 2 [Member] | ' | | ' | |
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis | ' | | ' | |
Available-for-sale securities measured at fair value on a recurring basis | 1,960 | | 2,074 | |
Mortgage-backed and asset-backed securities [Member] | Level 3 [Member] | ' | | ' | |
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis | ' | | ' | |
Available-for-sale securities measured at fair value on a recurring basis | 0 | | 0 | |
Closed-end bond funds [Member] | ' | | ' | |
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis | ' | | ' | |
Available-for-sale securities measured at fair value on a recurring basis | 16,682 | | 16,363 | |
Closed-end bond funds [Member] | Level 1 [Member] | ' | | ' | |
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis | ' | | ' | |
Available-for-sale securities measured at fair value on a recurring basis | 16,682 | | 16,363 | |
Closed-end bond funds [Member] | Level 2 [Member] | ' | | ' | |
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis | ' | | ' | |
Available-for-sale securities measured at fair value on a recurring basis | 0 | | 0 | |
Closed-end bond funds [Member] | Level 3 [Member] | ' | | ' | |
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis | ' | | ' | |
Available-for-sale securities measured at fair value on a recurring basis | 0 | | 0 | |
Preferred stock [Member] | ' | | ' | |
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis | ' | | ' | |
Available-for-sale securities measured at fair value on a recurring basis | 3,187 | | 3,142 | |
Preferred stock [Member] | Level 1 [Member] | ' | | ' | |
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis | ' | | ' | |
Available-for-sale securities measured at fair value on a recurring basis | 0 | | 0 | |
Preferred stock [Member] | Level 2 [Member] | ' | | ' | |
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis | ' | | ' | |
Available-for-sale securities measured at fair value on a recurring basis | 3,187 | | 3,142 | |
Preferred stock [Member] | Level 3 [Member] | ' | | ' | |
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis | ' | | ' | |
Available-for-sale securities measured at fair value on a recurring basis | $0 | | $0 | |
|
[1] | At September 30, 2014 and March 31, 2014, approximately $1.0 million and $1.1 million of the estimated fair value presented were mortgage-backed securities, respectively. |