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Debt instrument, revolving and term loan

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Letter Of Credit Usage Fee Maximum

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Letter Of Credit Usage Fee Minimum

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

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Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Amount of the required periodic payments applied to principal.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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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.

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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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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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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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Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer).

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Long-Term Debt - Narrative (Detail) (USD $)	3 Months Ended	12 Months Ended	0 Months Ended
Long-Term Debt - Narrative (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014	May 20, 2014	Sep. 18, 2014	Oct. 12, 2012	Apr. 17, 2014	Apr. 16, 2014	Jan. 15, 2015	Apr. 15, 2014	Jul. 01, 2013	Feb. 01, 2008	Dec. 22, 2006	Sep. 15, 2011
Debt Instrument [Line Items]
Credit facility, outstanding amount	$ 522,500,000us-gaap_LineOfCredit	$ 529,375,000us-gaap_LineOfCredit					$ 25,000,000.0us-gaap_LineOfCredit
Revolving and term loan	50,000,000.0bro_DebtInstrumentRevolvingAndTermLoan
Potential increased in line of credit facility						500,000,000.0
Unsecured revolving credit facility						800,000,000.0bro_UnsecuredRevolvingCreditFacility
Unsecured term loans						550,000,000.0us-gaap_UnsecuredLongTermDebt
Outstanding debt balance	1,173,510,000us-gaap_LongTermDebt	1,198,471,000us-gaap_LongTermDebt
5.370% senior notes, Series D, quarterly interest payments, balloon due 2015
Debt Instrument [Line Items]
Debt instrument interest rate stated percentage		5.37%
Current portion of senior notes	0	25,000,000						25,000,000
Debt instrument maturity year		2015
Credit Agreement
Debt Instrument [Line Items]
Credit facility, outstanding amount	550,000,000	550,000,000
Number of extension periods			2
Extension period			1 year
Unsecured revolving credit facility						1,350,000,000.0
First principal payment	6,900,000
Unsecured Senior Notes
Debt Instrument [Line Items]
Debt instrument interest rate stated percentage				4.20%
Debt instrument, face amount				500,000,000.0
Debt instrument maturity year				2024
Outstanding debt balance	500,000,000	500,000,000
Wells Fargo Revolver
Debt Instrument [Line Items]
Debt instrument, maturity date	Dec. 31, 2016
Potential increased in line of credit facility	75,000,000.0
Borrowings outstanding	0	0
Wells Fargo Revolver \| Beecher Acquisition
Debt Instrument [Line Items]
Credit facility, outstanding amount									50,000,000.0	50,000,000.0
Line of Credit \| Wells Fargo Revolver
Debt Instrument [Line Items]
Letter of credit usage fee, minimum	1.00%
Letter of credit usage fee, maximum	1.40%
LIBOR below base rate	1.00%
Availability fees, minimum	0.175%
Availability fees, maximum	0.25%
Term Loan
Debt Instrument [Line Items]
Credit facility, outstanding amount			550,000,000.0
Revolving Credit Facility
Debt Instrument [Line Items]
Credit facility, outstanding amount			375,000,000	475,000,000
Proceeds from lines of credit	0	0
Uncommitted Facility \| New Master Agreement
Debt Instrument [Line Items]
Credit facility, outstanding amount	0	0
Potential increased in line of credit facility					125,000,000
Issuance period					3 years
Maturity period	10 years
Master Agreement
Debt Instrument [Line Items]
Unsecured senior notes outstanding	125,000,000
Master Agreement \| Series C
Debt Instrument [Line Items]
Unsecured senior notes outstanding											25,000,000.0	25,000,000.0
Debt instrument interest rate stated percentage												5.66%
Master Agreement \| Series D
Debt Instrument [Line Items]
Debt instrument interest rate stated percentage											5.37%
Master Agreement \| Series E
Debt Instrument [Line Items]
Unsecured senior notes outstanding													$ 100,000,000.0
Debt instrument interest rate stated percentage													4.50%
LIBOR
Debt Instrument [Line Items]
30-day Adjusted LIBOR Rate	0.19%
Minimum \| Revolving Credit Facility
Debt Instrument [Line Items]
Facility fee	0.15%
Minimum \| LIBOR \| Term Loan
Debt Instrument [Line Items]
Debt instrument, variable interest rate	1.00%
Minimum \| LIBOR \| Line of Credit \| Wells Fargo Revolver
Debt Instrument [Line Items]
Debt instrument, variable interest rate	1.00%
Minimum \| LIBOR \| Revolving Credit Facility
Debt Instrument [Line Items]
Debt instrument, variable interest rate	0.85%
Maximum \| Revolving Credit Facility
Debt Instrument [Line Items]
Facility fee	0.25%
Maximum \| LIBOR \| Term Loan
Debt Instrument [Line Items]
Debt instrument, variable interest rate	1.75%
Maximum \| LIBOR \| Line of Credit \| Wells Fargo Revolver
Debt Instrument [Line Items]
Debt instrument, variable interest rate	1.40%
Maximum \| LIBOR \| Revolving Credit Facility
Debt Instrument [Line Items]
Debt instrument, variable interest rate	1.50%