Business Combinations - Acquisitions Accounted for Business Combinations (Detail) (USD $)	3 Months Ended
Mar. 31, 2014	Mar. 31, 2013
Business Combination, Separately Recognized Transactions [Line Items]
Cash Paid	$ 1,013,000	$ 61,000
Other Payable		(454,000)
Net Assets Acquired	1,293,000	(1,114,000)
Arrowhead General Insurance Agency Superholding Corporation [Member]
Business Combination, Separately Recognized Transactions [Line Items]
Net Assets Acquired		(454,000)
Insurcorp & GGM Investments LLC [Member]
Business Combination, Separately Recognized Transactions [Line Items]
Net Assets Acquired		(834,000)
Richard W. Endlar Insurance Agency, Inc. [Member]
Business Combination, Separately Recognized Transactions [Line Items]
Net Assets Acquired		220,000
Texas Security General Insurance Agency, Inc. [Member]
Business Combination, Separately Recognized Transactions [Line Items]
Net Assets Acquired		(107,000)
Other Acquisitions [Member]
Business Combination, Separately Recognized Transactions [Line Items]
Net Assets Acquired		61,000
2012 Acquisitions [Member]
Business Combination, Separately Recognized Transactions [Line Items]
Cash Paid		61,000
Other Payable		(454,000)
Recorded Earn-out Payable		(721,000)
Net Assets Acquired		(1,114,000)
2012 Acquisitions [Member] \| Arrowhead General Insurance Agency Superholding Corporation [Member] \| National Programs & Services [Member]
Business Combination, Separately Recognized Transactions [Line Items]
Date of Acquisition		Jan. 09, 2012
Other Payable		(454,000)
Net Assets Acquired		(454,000)
2012 Acquisitions [Member] \| Insurcorp & GGM Investments LLC [Member] \| Retail [Member]
Business Combination, Separately Recognized Transactions [Line Items]
Date of Acquisition		May 01, 2012
Recorded Earn-out Payable		(834,000)
Net Assets Acquired		(834,000)
2012 Acquisitions [Member] \| Richard W. Endlar Insurance Agency, Inc. [Member] \| Retail [Member]
Business Combination, Separately Recognized Transactions [Line Items]
Date of Acquisition		May 01, 2012
Recorded Earn-out Payable		220,000
Net Assets Acquired		220,000
2012 Acquisitions [Member] \| Texas Security General Insurance Agency, Inc. [Member] \| Wholesale Brokerage [Member]
Business Combination, Separately Recognized Transactions [Line Items]
Date of Acquisition		Sep. 01, 2012
Recorded Earn-out Payable		(107,000)
Net Assets Acquired		(107,000)
2012 Acquisitions [Member] \| Other Acquisitions [Member] \| Various [Member]
Business Combination, Separately Recognized Transactions [Line Items]
Cash Paid		61,000
Net Assets Acquired		61,000
2014 Acquisitions [Member] \| Retail [Member]
Business Combination, Separately Recognized Transactions [Line Items]
Cash Paid	1,013,000
Recorded Earn-out Payable	280,000
Net Assets Acquired	$ 1,293,000

Business Acquisition Cost Of Acquired Entity Other Payable

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- Definition

Business Acquisitions Contingent Consideration At Fair Value

+ References

No definition available.

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- Definition

Date when the acquirer obtains control of the acquiree, in CCYY-MM-DD format.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

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- Definition

Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

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