Shareholders Equity - Additional Information (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended									3 Months Ended		9 Months Ended		3 Months Ended	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013 Employee Stock Purchase Plan	Sep. 30, 2012 Employee Stock Purchase Plan	Sep. 30, 2013 Employee Stock Purchase Plan	Sep. 30, 2012 Employee Stock Purchase Plan	Sep. 30, 2013 401(k) Plan	Sep. 30, 2012 401(k) Plan	Sep. 30, 2013 Carrier Enterprise II	Jul. 30, 2011 Carrier Enterprise II	Sep. 30, 2013 Carrier Enterprise III	Jul. 02, 2012 Carrier Enterprise I	Jul. 01, 2009 Carrier Enterprise I	Sep. 30, 2013 Common Stock	Sep. 30, 2012 Common Stock	Sep. 30, 2013 Common Stock	Sep. 30, 2012 Common Stock	Sep. 30, 2013 Class B Common Stock	Sep. 30, 2013 Class B Common Stock
Stockholders Equity Note [Line Items]
Cash dividends paid per share of Common and Class B common stock	$ 0.25	$ 0.62	$ 0.75	$ 1.86
Shares of non-vested restricted stock granted	31,500	53,000	119,043	111,301
Stock options exercised, shares																34,700	18,250	44,200	109,084
Stock options exercised, value																$ 1,162	$ 571	$ 1,539	$ 3,380
Stock delivered as payment to satisfy tax withholdings, shares																	3,592		23,159	5,448	5,448
Stock delivered as payment to satisfy tax withholdings, market value																	276		1,725	490	490
Common stock issued under employee stock purchase plan, shares					1,944	3,126	5,870	8,720
Common stock issued under employee stock purchase plan, net proceeds					160	217	459	597
Common stock issued to profit sharing retirement plan, shares									22,551	26,991
Non-cash contribution for 401(k) plan									$ 1,689	$ 1,772
Controlling interest, ownership percentage											60.00%	60.00%	60.00%	70.00%	60.00%
Noncontrolling interest, ownership percentage	40.00%		40.00%									40.00%			40.00%