Minimum exercise price on put/call option agreement for the remaining ownership interest in Copal Partners Ltd.

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Amount of potential cash payments that could result from the contingent consideration arrangement.

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Fair Value of the liabilities incurred by the acquirer to former owners of the acquiree, including the fair value of any contingent consideration. If liabilities transferred as consideration remain within the combined entity after the business combination (for example, because the assets or liabilities were transferred to the acquiree rather than to its former owners), and the acquirer therefore retains control of them; in that situation, the acquirer measures those liabilities at their carrying amounts immediately before the acquisition date.

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The total cost of the acquired entity including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, the fair value of the liabilities assumed, and direct costs of the acquisition.

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Amount of direct costs of the business combination including legal, accounting, and other costs incurred to consummate the business acquisition.

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Percentage of voting equity interests acquired in the business combination.

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The cash inflow associated with the acquisition of business during the period (for example, cash that was held by the acquired business).

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The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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The fair value of notes issued in noncash investing and financing activities.

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Acquisitions - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	1 Months Ended				1 Months Ended	6 Months Ended	12 Months Ended
	Nov. 04, 2011	Dec. 16, 2011 Barrie & Hibbert Limited	Nov. 04, 2011 Copal Partners	Nov. 04, 2011 Copal Partners Maximum	Nov. 04, 2011 Copal	Jun. 30, 2012 Copal	Dec. 31, 2011 Copal	May 06, 2011 KIS Pricing, Inc.	Nov. 04, 2011 Copal Group Of Companies
Business Acquisition [Line Items]
Purchase price		$ 79.5
Acquired cash		10
Acquired interest			67.00%		100.00%				75.00%
Remaining ownership interest			33.00%
Option minimum exercise price	46,000,000
Non-interest bearing note issued			14.2		14.2	14.2	14.2
Contingent consideration liability assumed	6.8		6.8
Contingent payment				2.5
Amount related to transaction cost			$ 7
Additional direct equity investment in KIS pricing								16.00%