Derivative Instruments - Effect of Interest Rate Swaps on Consolidated Statements of Comprehensive Income Loss (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended				9 Months Ended
	Sep. 30, 2014		Sep. 30, 2013		Sep. 30, 2014		Sep. 30, 2013
Effect of Derivatives on Statement of Operations and Comprehensive Income:
Realized gains (losses) on interest rate swaps	$ (169,083)	[1],[2]	$ (227,909)	[1],[2]	$ (650,452)	[1],[2]	$ (666,112)	[1],[2]
Realized gain (losses) on termination of interest rate swaps	0		(36,658)		(779,333)		(88,685)
Unrealized gains (losses) on interest rate swaps	$ 98,593		$ 6,343		$ (75,287)		$ 1,441,099

[1] Interest expense related to the Company's interest rate swaps is recorded in Realized gains (losses) on interest rate swaps.

[2] Interest expense related to the Company's interest rate swaps is recorded in Realized gains (losses) on interest rate swaps on the Consolidated Statements of Comprehensive Income (Loss).