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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For receivables acquired in a business combination, excluding certain loans and debt securities acquired in a transfer (as defined), this element represents the gross contractual amounts receivable, by major class of receivable, such as loans, direct finance leases (as defined), and any other class of receivables.

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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		0 Months Ended			0 Months Ended	12 Months Ended			0 Months Ended
	Dec. 31, 2013	Dec. 16, 2011 Barrie & Hibbert Limited	Nov. 04, 2011 Copal Partners	Dec. 31, 2011 Copal Partners	Nov. 04, 2011 Copal	Dec. 31, 2013 Copal	Nov. 04, 2011 Copal Maximum	Nov. 04, 2011 Copal Group of Companies	Dec. 11, 2013 Amba	Dec. 31, 2013 Amba
Business Acquisition [Line Items]
Purchase price		$ 79.5
Acquired cash		10.0	7.0						16.0
Amount related to transaction cost		1.0		7.0						1.0
Acquired interest			67.00%		100.00%			75.00%
Remaining ownership interest	33.00%		(33.00%)
Option minimum exercise price			(46.0)			46.0
Non-interest bearing note issued			14.2		14.2	14.2
Contingent consideration liability assumed			6.8
Contingent cash payment	2.5						2.5
Additional direct equity investment										100.00%
Acquired receivables gross contractual amount										$ 6.0