DEBT OBLIGATIONS AND CREDIT FACILITIES - Debt Obligations (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
Debt Instrument [Line Items]
Debt obligations	$ 585,714,000	$ 615,179,000
5.03% [Member]
Debt Instrument [Line Items]
Debt obligations	10,714,000	21,429,000
6.09% [Member]
Debt Instrument [Line Items]
Debt obligations	50,000,000	50,000,000
5.82% [Member]
Debt Instrument [Line Items]
Debt obligations	50,000,000	50,000,000
6.75% [Member]
Debt Instrument [Line Items]
Debt obligations	250,000,000	250,000,000
2.50% Debt, Term Loan Two [Member]
Debt Instrument [Line Items]
Debt obligations	$ 225,000,000	$ 243,750,000