Operating Segments - Narrative (Detail) $ in Millions	Jun. 30, 2016 USD ($) nonconsolidated_partner_company	Dec. 31, 2015 USD ($)
Segment Reporting Information [Line Items]
Non-consolidated partner companies \| nonconsolidated_partner_company	27
Other Items
Segment Reporting Information [Line Items]
Total assets included cash, cash equivalents, cash held in escrow, and marketable securities \| $	$ 91.4	$ 73.6

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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