Debt - Additional Information 3 (Detail)	12 Months Ended						12 Months Ended		12 Months Ended		0 Months Ended				12 Months Ended				0 Months Ended		12 Months Ended							12 Months Ended					12 Months Ended
	Dec. 31, 2013 USD ($)	Dec. 31, 2012 USD ($)	Dec. 31, 2011 USD ($)	Dec. 31, 2013 Propel Facility [Member] USD ($)	Dec. 27, 2013 Propel Facility [Member] USD ($)	Dec. 31, 2012 Propel Facility [Member]	Dec. 31, 2013 Propel Wells Fargo Facility [Member] USD ($)	May 09, 2013 Propel Wells Fargo Facility [Member] USD ($)	Dec. 31, 2013 Cabot Corporation [Member] USD ($)	Dec. 31, 2013 Cabot Corporation [Member] GBP (£)	Sep. 20, 2012 Cabot 2019 Notes [Member] USD ($)	Sep. 20, 2012 Cabot 2019 Notes [Member] GBP (£)	Aug. 02, 2013 Cabot 2020 Notes [Member] USD ($)	Aug. 02, 2013 Cabot 2020 Notes [Member] GBP (£)	Dec. 31, 2013 J Bridge PECs [Member] USD ($)	Dec. 31, 2013 J Bridge PECs [Member] GBP (£)	Dec. 31, 2013 2011 Senior Secured Notes [Member] USD ($)	Dec. 31, 2013 2010 Senior Secured Notes [Member] USD ($)	Feb. 07, 2014 Subsequent Event [Member] Marlin Acquisition [Member] USD ($)	Feb. 07, 2014 Subsequent Event [Member] Marlin Acquisition [Member] GBP (£)	Dec. 31, 2013 LIBOR [Member] Propel Facility [Member] Minimum [Member]	Dec. 31, 2013 LIBOR [Member] Propel Facility [Member] Maximum [Member]	Dec. 31, 2013 LIBOR [Member] Propel Wells Fargo Facility [Member]	Dec. 31, 2013 Prime Rate [Member] Propel Facility [Member] Minimum [Member]	Dec. 31, 2013 Prime Rate [Member] Propel Facility [Member] Maximum [Member]	Sep. 20, 2012 Cabot Credit Agreement [Member] USD ($)	Sep. 20, 2012 Cabot Credit Agreement [Member] GBP (£)	Dec. 31, 2013 Cabot Credit Facility [Member] USD ($)	Jun. 28, 2013 Cabot Credit Facility [Member] GBP (£)	Jun. 28, 2012 Cabot Credit Facility [Member] USD ($)	Feb. 07, 2014 Cabot Credit Facility [Member] Subsequent Event [Member] Marlin Acquisition [Member] USD ($)	Feb. 07, 2014 Cabot Credit Facility [Member] Subsequent Event [Member] Marlin Acquisition [Member] GBP (£)	Dec. 31, 2013 Cabot Credit Facility [Member] LIBOR [Member]
Debt Instrument [Line Items]
Senior Secured Notes	$ 58,750,000	$ 72,500,000									$ 438,400,000	£ 265,000,000	$ 151,700,000	£ 100,000,000
Senior Secured Notes, aggregate amount	75,000,000																25,000,000	50,000,000
Debt instrument, interest rate											10.375%	10.375%	8.375%				7.375%	7.75%
Senior Secured Notes, periodic principal repayment																	1,250,000	2,500,000
Frequency of repayment, Senior Secured Notes																	Quarterly
Debt instrument maturity date											2019	2019					2018	2017
Revolving credit facility, maximum borrowing capacity				160,000,000	200,000,000			100,000,000																		82,700,000	50,000,000		85,000,000	140,600,000
Debt instrument, maturity date				2015-05			2017-05
Basis spread on variable rate																					3.00%	3.75%	3.25%	0.00%	0.75%								4.00%
Borrowing base of the face value of the tax lien collateralized notes				90.00%
Credit facility, accordion feature				40,000,000
Credit facility, outstanding amount				152,300,000																								0			122,300,000	75,000,000
Weighted average interest rate	3.11%	4.06%		3.19%		3.37%	3.64%
Additional draws	0
Debt instrument, term							4 years																					5 years
Amount outstanding	496,600,000						18,300,000
Debt instrument interest payment date											Interest on the Cabot 2019 Notes is payable semi-annually, in arrears, on April 1 and October 1 of each year	Interest on the Cabot 2019 Notes is payable semi-annually, in arrears, on April 1 and October 1 of each year	Interest on the Cabot 2020 Notes is payable semi-annually, in arrears, on February 1 and August 1 of each year, beginning on February 1, 2014
Debt issuance cost													4,900,000
Repayment of senior credit facility	630,163,000	289,673,000	143,000,000						113,800,000	75,000,000
Repayment of J Bridge PECs	39,743,000														37,900,000	25,000,000
Line of credit facility expiry date																												Sep. 01, 2017
LTV ratio																												0.75%
Aggregate purchase price																			$ 481,000,000	£ 295,000,000