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Debt - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified |  |  | 12 Months Ended |  |  | 0 Months Ended |  | 12 Months Ended | 0 Months Ended | 12 Months Ended | 0 Months Ended
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Mar. 31, 2014 | Mar. 31, 2013 | Mar. 31, 2014 Revolving credit facility [Member] Contract | Mar. 31, 2013 Revolving credit facility [Member] | Dec. 03, 2010 Revolving credit facility [Member] | Mar. 24, 2014 Revolving credit facility [Member] Letter of Credit [Member] | Mar. 31, 2014 Revolving credit facility [Member] Letter of Credit [Member] | Mar. 31, 2014 Revolving credit facility [Member] Maximum [Member] | Mar. 24, 2014 Revolving credit facility [Member] Maximum [Member] Letter of Credit [Member] | Mar. 31, 2014 Revolving credit facility [Member] Minimum [Member] | Mar. 24, 2014 Revolving credit facility [Member] Minimum [Member] Letter of Credit [Member]
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Short-term borrowings outstanding | $ 0 | $ 0 |  |  |  |  |  |  |  |  |
Line of credit |  |  |  |  | 25,000 | 5,000 |  |  |  |  |
Maximum limit of credit facility |  |  |  |  | 50,000 |  |  |  |  |  |
Term period of agreement |  |  | 3 years |  |  |  |  |  |  |  |
Number of automatic one year extensions in term period |  |  | 2 |  |  |  |  |  |  |  |
Term period of agreement, automatic extension |  |  | 1 year |  |  |  |  |  |  |  |
Unused commitment fee for borrowing |  |  |  |  |  |  |  | 0.375% |  | 0.20% |
Bank's prime rate |  |  | 3.25% | 3.25% |  |  |  |  |  |  |
Interest rate description |  |  | Interest at either (i) a rate equal to the bank's prime rate; or (ii) a rate equal to LIBOR plus a margin. |  |  |  |  |  |  |  |
LIBOR Plus a margin range |  |  |  |  |  |  |  | 2.00% |  | 1.00% |
Fee for outstanding letters of credit |  |  |  |  |  |  |  | 1.25% | 1.25% | 0.75% | 0.75%
Fix rate to reduce fee on outstanding |  |  | 0.55% |  |  |  |  |  |  |  |
Availability under the line of credit |  |  | 9,527 |  |  |  | 5,000 |  |  |  |
Maximum funded debt to EBITDA ratio |  |  | 3.5 |  |  | 3.5 |  |  |  |  |
Minimum earnings to interest ratio |  |  | 4.0 |  |  | 4.0 |  |  |  |  |
Maximum funded debt to EBITDA ratio under condition one |  |  | 2.0 |  |  |  |  |  |  |  |
Dividend pay amount |  |  | 25.00% |  |  |  |  |  |  |  |
Minimum funded debt to EBITDA ratio under condition two |  |  | 2.0 |  |  |  |  |  |  |  |
Assets book value |  |  | 104,451 |  |  |  |  |  |  |  |
Annual facility fees |  |  |  |  |  | 0.375% |  |  |  |  |
Long-term debt payment requirements over the next five years | $ 0 |  |  |  |  |  |  |  |  |  |

X
- Definition Book value of assets included in the consolidated balance sheet that have been pledged to secure borrowings under the credit facility. + References No definition available. + Details
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- Definition The fixed rate fee for outstanding letters of credit that are secured by cash and cash equivalents. + References No definition available. + Details
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- Definition The fee, expressed as a percentage of the standby letter of credit amount, incurred for the issuance of a standby letter of credit. + References No definition available. + Details
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- Definition Line of credit facility bank prime rate. + References No definition available. + Details
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- Definition Line of credit facility basis spread on variable rate. + References No definition available. + Details
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- Definition Line Of Credit Facility Maturity Extended Period + References No definition available. + Details
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- Definition Line of credit facility maturity period. + References No definition available. + Details
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- Definition Line of credit facility number of extensions for maturity period. + References No definition available. + Details
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- Definition Maximum funded debt to earnings before interest taxes depreciation and amortization ratio. + References No definition available. + Details
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- Definition Maximum funded debt to earnings before Interest taxes depreciation and amortization ratio under condition one. + References No definition available. + Details
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- Definition Minimum earnings before interest expense and income taxes to interest ratio. + References No definition available. + Details
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- Definition Minimum funded debt to EBITDA ratio under condition 2. + References No definition available. + Details
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- Definition Percentage of net income allowed for payment of dividends under condition two. + References No definition available. + Details
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- Details
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- Definition The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used. + References No definition available. + Details
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- Definition Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility. + 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 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 22 -Article 5 + Details
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- Definition Description of the interest rate for the amounts borrowed under the credit facility, including the terms and the method for determining the interest rate (for example, fixed or variable, LIBOR plus a percentage, increasing rate, timing of interest rate resets, remarketing provisions). + 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 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 22 -Article 5 + Details
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- Definition Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility. + 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 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 22 -Article 5 + Details
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- Definition Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding). + 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 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 22 -Article 5 + Details
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- Definition The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility. + References No definition available. + Details
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- Definition Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 16 -Article 7 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 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 210.9-03.16) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 16 -Article 9 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 20, 22 -Article 5 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.16) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 + Details
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- Definition Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19 -Subparagraph a -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(a)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 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 210.9-03.13) -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 -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.(a),16(a)(1)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 16 -Subparagraph a(1) -Article 7 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 13 -Subparagraph 2, 3 -Article 9 + Details
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