v2.4.0.8

AFS, Debt Maturities (Details) (USD $) In Thousands, unless otherwise specified | 6 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2014 | Mar. 31, 2014
Schedule of available-for-sale securities, debt maturities [Line Items] |  |
Available-for-sale, adjusted cost | $ 1,643,964 | $ 1,677,422
Available-for-sale, gross unrealized gains | 2,345 | 3,462
Available-for-sale, gross unrealized losses | (3,362) | (3,990)
Available-for-sale, estimated fair value | 1,642,947 | 1,676,894
Due in one year or less [Member] |  |
Schedule of available-for-sale securities, debt maturities [Line Items] |  |
Available-for-sale, adjusted cost | 250,615 |
Available-for-sale, gross unrealized gains | 742 |
Available-for-sale, gross unrealized losses | (5) |
Available-for-sale, estimated fair value | 251,352 |
Due after one year and through five years [Member] |  |
Schedule of available-for-sale securities, debt maturities [Line Items] |  |
Available-for-sale, adjusted cost | 1,264,898 |
Available-for-sale, gross unrealized gains | 1,552 |
Available-for-sale, gross unrealized losses | (2,227) |
Available-for-sale, estimated fair value | 1,264,223 |
Due after five years and through ten years [Member] |  |
Schedule of available-for-sale securities, debt maturities [Line Items] |  |
Available-for-sale, adjusted cost | 112,436 |
Available-for-sale, gross unrealized gains | 51 |
Available-for-sale, gross unrealized losses | (1,130) |
Available-for-sale, estimated fair value | 111,357 |
Due after ten years [Member] |  |
Schedule of available-for-sale securities, debt maturities [Line Items] |  |
Available-for-sale, adjusted cost | 9,825 |
Available-for-sale, gross unrealized gains | 0 |
Available-for-sale, gross unrealized losses | 0 |
Available-for-sale, estimated fair value | 9,825 |
Total Maturities [Member] |  |
Schedule of available-for-sale securities, debt maturities [Line Items] |  |
Available-for-sale, adjusted cost | 1,637,774 |
Available-for-sale, gross unrealized gains | 2,345 |
Available-for-sale, gross unrealized losses | (3,362) |
Available-for-sale, estimated fair value | $ 1,636,757 |

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- Definition Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26610-111562 + Details
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- Definition This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.2) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Amount of unrealized gain before deducting unrealized loss on investments in debt and equity securities classified as available-for-sale securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563 + Details
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- Definition Amount of unrealized loss before deducting unrealized gain on investments in available-for-sale securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563 + Details
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