Fair Value Measurement - Quantitative Information About Level 3 Fair Value Measurements for Financial Instruments Measured at Fair Value on Nonrecurring Basis (Interest rate caps) (Detail) (USD $) In Thousands, unless otherwise specified	9 Months Ended	12 Months Ended
	Sep. 30, 2014	Dec. 31, 2013
Fair Value Inputs Assets Quantitative Information [Line Items]
Fair Value	$ 268	$ 546
Valuation Technique	Discounted cash flow	Discounted cash flow
Minimum [Member] | Discounted Cash Flow [Member]
Fair Value Inputs Assets Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	0.40%	0.35%
Maximum [Member] | Discounted Cash Flow [Member]
Fair Value Inputs Assets Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	1.18%	1.18%