Operating Segments - Narrative (Detail) (USD $)
In Millions, unless otherwise specified |
Dec. 31, 2014
partner_company
|
Dec. 31, 2013
|
Jun. 30, 2014
|
Mar. 31, 2014
|
---|---|---|---|---|
Segment Reporting Information [Line Items] | ||||
Non-consolidated partner companies | 24 | |||
Other Segments [Member] | ||||
Segment Reporting Information [Line Items] | ||||
Total assets included cash, cash equivalents, cash held in escrow and marketable securities | 156.5 | $ 183.7 | ||
Bridgevine, Inc. [Member] | ||||
Segment Reporting Information [Line Items] | ||||
Ownership interest under equity method, percentage | 17.30% | 22.70% |