Summarized Aggregate Financial Information for Equity Investees (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Subsidiary, Sale of Stock [Line Items]
Revenues	$ 66,145	$ 70,896	$ 73,450
Net earnings	11,037	4,326	6,976
Total assets	52,500	57,972	31,767
Notes payable	23,681	23,533	1,119
Stockholders' equity	$ 12,758	$ 12,524	$ 16,027