Equity-Based Compensation - Additional Information. (Detail) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended			12 Months Ended											12 Months Ended																					1 Months Ended		12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2012 Non-Management Directors (Director Plan)	Dec. 31, 2012 Deferred Stock Units	Dec. 31, 2011 Deferred Stock Units	Dec. 31, 2010 Deferred Stock Units	Dec. 31, 2012 Deferred Stock Units Non-Management Directors (Director Plan) M	Dec. 31, 2012 Deferred Stock Units Selling, General and Administrative Expenses	Dec. 31, 2011 Deferred Stock Units Selling, General and Administrative Expenses	Dec. 31, 2010 Deferred Stock Units Selling, General and Administrative Expenses	Dec. 31, 2012 SARs	Dec. 31, 2011 SARs	Dec. 31, 2010 SARs	Dec. 31, 2012 Restricted Stock Award	Dec. 31, 2011 Restricted Stock Award	Dec. 31, 2010 Restricted Stock Award	Dec. 31, 2012 Restricted Stock Award Non-Management Directors (Director Plan)	Dec. 31, 2012 Restricted Stock Award Employee	Dec. 31, 2012 Restricted Stock Award Non-Management Independent Directors	Dec. 31, 2012 Restricted Stock Award Executives of a Consolidated Subsidiary	Dec. 31, 2011 Restricted Stock Award Grant Date One	Dec. 31, 2012 Restricted Stock Award Grant Date One Employee	Dec. 31, 2011 Restricted Stock Award Grant Date Two	Dec. 31, 2012 Restricted Stock Award Grant Date Two Employee	Dec. 31, 2011 Restricted Stock Award Grant Date Three	Dec. 31, 2011 Restricted Stock Award Grant Date Three Condition One	Dec. 31, 2011 Restricted Stock Award Grant Date Three Condition Two	Dec. 31, 2011 Restricted Stock Award Grant Date Three Condition Three	Dec. 31, 2011 Restricted Stock Award Grant Date Three Chief Executive Officer	Dec. 31, 2011 Restricted Stock Award Grant Date Three President	Dec. 31, 2011 Restricted Stock Award Minimum Grant Date Three	Dec. 31, 2011 Restricted Stock Award Minimum Grant Date Three Performance based Vesting Condition	Dec. 31, 2011 Restricted Stock Award Maximum Grant Date Three	Dec. 31, 2012 Stock Options Consolidated Entities	Dec. 31, 2012 Stock Options Minimum	Dec. 31, 2012 Stock Options Maximum	Dec. 31, 2010 Restricted Stock Grants, Twenty Ten	Dec. 31, 2012 Restricted Stock Grants, Twenty Ten First Grant	Dec. 31, 2011 Restricted Stock Grants, Twenty Ten First Grant	Dec. 31, 2012 Restricted Stock Grants, Twenty Ten Second Grant	Dec. 31, 2011 Restricted Stock Grants, Twenty Ten Second Grant	Dec. 31, 2012 Performance Shares Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards vesting period	36 months											4 years																								1 year	4 years
Expiry period of incentive or non-qualified stock options granted from date of grant																																				8 years	10 years
Common Stock reserved under for possible future issuance	365,208
SARs vesting on the first anniversary	25.00%
Remaining SARs vesting equally each month	75.00%
Subsequent vesting of remaining SARs, period	36 months
SARs exercisable												3,468,805	2,979,552	2,298,884
SARs weighted average base price												$ 7.53	$ 7.42	$ 7.61
SARs expected to vest												869,445
Options exercisable	1,729	183,082	310,919
Options, weighted average exercise price	$ 6.94	$ 6.25	$ 16.65
Additional stock options expect to vest	21
Restricted stock awards vested															$ 1.3	$ 0.2	$ 0.1
Shares surrendered for satisfying withholding taxes															39,817	3,351	2,777
Restricted stock awards granted															1.1	10.8	0.4
Number of restricted stock grants																3			3																			2
Restricted stock awards granted																		30,750	69,875	18,750	28,348	15,035		66,875		1,100,000				550,000	550,000												130,440
Vesting percentage of shares of restricted stock granted																						100.00%	12.50%		87.50%
Vesting period of shares of restricted stock granted																						2018-05
Annual vesting percentage of shares of restricted stock granted																								25.00%															25.00%		25.00%
Shares of restricted stock to vest upon achievement of certain condition																											183,334	183,333	183,333				91,667
Minimum trailing twelve-month consolidated revenue to be achieved																																500.0
Minimum trailing twelve-month consolidated adjusted earnings before interest, taxes, depreciation and amortization to be achieved																										70.0
Percentage of financial targets to be achieved for participants to receive award																																75.00%		100.00%
Thirty-day volume weighted average price per share of Common Stock																																$ 25.00
Per share stock price target																										$ 25.00
Expected target achievement date for restricted stock granted to vest																										Dec. 31, 2015
Percentage of granted shares of restricted stock vested																																								25.00%		25.00%
Restricted stock unvested															1,217,463	1,225,785
Outstanding restricted shares expected to vest															1,208,786
Restricted stock awards, fair value																		0.4																									1.7
Awards vesting period								29,250
Deferred Stock Units, issued under director plan				400,000
DSUs issued					32,923	13,571	25,847
Expense associated with these DSUs									$ 0.3	$ 0.2	$ 0.2
Equity-based compensation awards vesting on the first anniversary																																			25.00%
Remaining Equity-based compensation awards vesting equally each month																																			75.00%