Long-Term Debt - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
Apr. 30, 2014	Apr. 30, 2013
Debt Instrument [Line Items]
Financial covenants amount	$ 50.0
Interest rate description	Borrowings under the Facility bear interest, at the election of the Company, at the London Interbank Offered Rate (“LIBOR”) plus the applicable margin or the base rate plus the applicable margin. The base rate is the highest of (i) the published prime rate, (ii) the federal funds rate plus 1.50%, or (iii) one month LIBOR plus 1.50%. The applicable margin is based on a percentage per annum determined in accordance with a specified pricing grid based on the total funded debt to adjusted EBITDA ratio. For LIBOR loans, the applicable margin will range from 0.50% to 1.50% per annum, while for base rate loans the applicable margin will range from 0.00% to 0.25% per annum. The Company is required to pay a quarterly commitment fee of 0.25% to 0.35% on the Facility’s unused commitments based on the Company’s funded debt to adjusted EBITDA ratio.
Covenant description	The financial covenants include a maximum consolidated funded debt to adjusted EBITDA ratio and a minimum adjusted EBITDA. As of April 30, 2013, the Company is in compliance with its financial covenants. In addition, there is a domestic liquidity requirement that the Company maintain $50.0 million in unrestricted cash and/or marketable securities (excluding any marketable securities that are held in trust for the settlement of the Company’s obligation under certain deferred compensation plans) as a condition to consummating permitted acquisitions, paying dividends to our shareholders and share repurchases of our common stock.
Dividend payable subject to certain conditions	50.0
Long-term debt	0	0
Standby Letters of Credit
Debt Instrument [Line Items]
Long-term debt arrangement	2.8	2.7
Previous Facility, restricted cash	0	2.9
Minimum
Debt Instrument [Line Items]
Quarterly Commitment Fees on the Facility's unused commitments	0.25%
Maximum
Debt Instrument [Line Items]
Quarterly Commitment Fees on the Facility's unused commitments	0.35%
Federal Funds Rate
Debt Instrument [Line Items]
Applicable margin on variable interest rate	1.50%
London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Applicable margin on variable interest rate	1.50%
London Interbank Offered Rate (LIBOR) \| Minimum
Debt Instrument [Line Items]
Applicable margin on variable interest rate	0.50%
London Interbank Offered Rate (LIBOR) \| Maximum
Debt Instrument [Line Items]
Applicable margin on variable interest rate	1.50%
Base Rate Loans \| Minimum
Debt Instrument [Line Items]
Applicable margin on variable interest rate	0.00%
Base Rate Loans \| Maximum
Debt Instrument [Line Items]
Applicable margin on variable interest rate	0.25%
Revolving Credit Facility
Debt Instrument [Line Items]
Senior Unsecured Revolving Facility, maximum borrowing capacity	75.0
Senior Unsecured Revolving Facility, additional borrowing capacity	50.0
Senior Unsecured Revolving Facility, maturity date	Jan. 18, 2018
Revolving Credit Facility \| Letter of Credit
Debt Instrument [Line Items]
Senior Unsecured Revolving Facility, maximum borrowing capacity	15.0
Other Financial Institutions \| Standby Letters of Credit
Debt Instrument [Line Items]
Long-term debt arrangement	1.5	1.4
Csv Of Coli Contracts
Debt Instrument [Line Items]
Outstanding policy loans	$ 72.9	$ 73.3
Csv Of Coli Contracts \| Minimum
Debt Instrument [Line Items]
Interest payable fixed and variable rates	4.76%
Csv Of Coli Contracts \| Maximum
Debt Instrument [Line Items]
Interest payable fixed and variable rates	8.00%

Line Of Credit Facility Additional Increase In Borrowing Capacity

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The amount the Company must maintain of unrestricted cash and or marketable securities (excluding any marketable securities that are held in trust for the settlement of obligations under certain deferred compensation plans) as a condition of consummating permitted acquisitions, paying dividends to shareholders and repurchases of our common stock.

+ References

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Maximum Permissable Dividends

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Policy Loans Payable

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Description of minimum financial levels (for example, tangible net worth and working capital) and achievement of certain financial ratios (for example, working capital ratio and debt service coverage ratio), and adherence to certain clauses which generally require or restrict certain actions (for example, entering into a debt arrangement with equal or greater seniority, and selling or discontinuing a certain business segment or material subsidiary) to be in compliance with the covenant clauses of the debt agreement. May also include a discussion of the adverse consequences that would result if the entity violates or fails to satisfy the covenants.

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The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

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The average effective interest rate during the reporting period.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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Date the credit facility terminates, in CCYY-MM-DD format.

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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.

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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.

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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.

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The carrying amounts of cash and cash equivalent items which are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against short-term borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. For a classified balance sheet represents the current portion only (the noncurrent portion has a separate concept); there is a separate and distinct element for unclassified presentations.

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