XML 16 R33.htm IDEA: XBRL DOCUMENT
v2.4.1.9

Investment Securities Text Figures (Details) (USD $) | 9 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2014 | Mar. 31, 2014
Schedule of Investments [Line Items] |  |  |  |
Number of agencies with unrealized loss more than 12 months | 8carv_Numberofagencieswithunrealizedlossmorethan12months |  |  |
Available-for-sale | $ 100,448,000us-gaap_AvailableForSaleSecurities |  | $ 89,461,000us-gaap_AvailableForSaleSecurities |
Percentage Available-for-sale Securities | 89.10%carv_PercentageAvailableForSaleSecurities |  |  |
Held-to-maturity | 12,253,000us-gaap_HeldToMaturitySecurities |  | 9,029,000us-gaap_HeldToMaturitySecurities |
Held-to-maturity Securities, Amortized Cost | 12,253,000us-gaap_HeldToMaturitySecuritiesAmortizedCostBeforeOtherThanTemporaryImpairment | [1] | 9,029,000us-gaap_HeldToMaturitySecuritiesAmortizedCostBeforeOtherThanTemporaryImpairment | [1]
Percentage Held-to-maturity Securities | 10.90%carv_PercentageHeldToMaturitySecurities |  |  |
Trading Securities | 0us-gaap_TradingSecurities |  |  |
Number of securities with unrealized loss | 31carv_NumberOfSecuritiesWithUnrealizedLoss |  | 35carv_NumberOfSecuritiesWithUnrealizedLoss |
US Government Agency Securities |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Percentage Available-for-Sale, Continuos Unrealized Loss Position | 68.90%carv_PercentageAvailableForSaleContinuosUnrealizedLossPosition / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USGovernmentAgenciesDebtSecuritiesMember |  |  |
Available-for-sale | 56,535,000us-gaap_AvailableForSaleSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USGovernmentAgenciesDebtSecuritiesMember |  | 52,189,000us-gaap_AvailableForSaleSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USGovernmentAgenciesDebtSecuritiesMember |
Mortgage-backed securities |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Percentage Available-for-Sale, Continuos Unrealized Loss Position | 31.10%carv_PercentageAvailableForSaleContinuosUnrealizedLossPosition / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_MortgageBackedSecuritiesMember |  |  |
Number of MBS with unrealized loss more than 12 months | 15carv_NumberOfMbsWithUnrealizedLossMoreThan12Months / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_MortgageBackedSecuritiesMember |  |  |
Available-for-sale | 27,689,000us-gaap_AvailableForSaleSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_MortgageBackedSecuritiesMember |  | 27,741,000us-gaap_AvailableForSaleSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_MortgageBackedSecuritiesMember |
Held-to-maturity Securities, Amortized Cost |  |  | $ 8,822,000us-gaap_HeldToMaturitySecuritiesAmortizedCostBeforeOtherThanTemporaryImpairment / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_MortgageBackedSecuritiesMember | [1]
[1] | * The carrying amount and amortized cost are the same for all held-to-maturity securities, as no OTTI has been recorded.

X
- Definition Number of agencies with unrealized loss more than 12 months + References No definition available. + Details
Name: | carv_Numberofagencieswithunrealizedlossmorethan12months
Namespace Prefix: | carv_
Data Type: | xbrli:pureItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number of MBS with unrealized loss more than 12 months + References No definition available. + Details
Name: | carv_NumberOfMbsWithUnrealizedLossMoreThan12Months
Namespace Prefix: | carv_
Data Type: | xbrli:pureItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of securities with unrealized loss + References No definition available. + Details
Name: | carv_NumberOfSecuritiesWithUnrealizedLoss
Namespace Prefix: | carv_
Data Type: | xbrli:pureItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage Available-for-Sale, Continuos Unrealized Loss Position + References No definition available. + Details
Name: | carv_PercentageAvailableForSaleContinuosUnrealizedLossPosition
Namespace Prefix: | carv_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Percentage Available-for-sale Securities + References No definition available. + Details
Name: | carv_PercentageAvailableForSaleSecurities
Namespace Prefix: | carv_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Percentage Held-to-maturity Securities + References No definition available. + Details
Name: | carv_PercentageHeldToMaturitySecurities
Namespace Prefix: | carv_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- 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
Name: | us-gaap_AvailableForSaleSecurities
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.1) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.6) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
Name: | us-gaap_HeldToMaturitySecurities
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount before other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity. + References No definition available. + Details
Name: | us-gaap_HeldToMaturitySecuritiesAmortizedCostBeforeOtherThanTemporaryImpairment
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_ScheduleOfInvestmentsLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of investments in debt and equity securities and other forms of securities that provide ownership interests classified as trading. + References Reference 1: 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 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26626-111562 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.4) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Trading Securities -URI http://asc.fasb.org/extlink&oid=6526789 + Details
Name: | us-gaap_TradingSecurities
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_MortgageBackedSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_USGovernmentAgenciesDebtSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |