Long-Lived Asset Impairment Charges (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Impaired Long-Lived Assets Held and Used [Line Items]
Impairment of long-lived assets	$ 633	$ 4,510	$ 4,955	$ 5,294
U.S. Operating Segment
Impaired Long-Lived Assets Held and Used [Line Items]
Impairment of long-lived assets	$ 633	$ 4,510	3,963	$ 5,294
US Intangible Assets
Impaired Long-Lived Assets Held and Used [Line Items]
Impairment of long-lived assets			$ 992