USE OF DERIVATIVE FINANCIAL INSTRUMENTS, OFFSETTING DISCLOSURES AND CHANGES IN OTHER COMPREHENSIVE INCOME BY COMPONENT - Schedule of Swap Agreements (Detail) (USD $)	6 Months Ended													12 Months Ended			3 Months Ended	6 Months Ended	3 Months Ended	6 Months Ended	3 Months Ended	6 Months Ended
	Jun. 30, 2014	Jun. 30, 2014 Interest Rate SWAP Currently-Paying Contracts [Member]	Jun. 30, 2014 Interest Rate SWAP Currently-Paying Contracts [Member] Third Quarter 2014 [Member]	Jun. 30, 2014 Interest Rate SWAP Currently-Paying Contracts [Member] Fourth Quarter 2014 [Member]	Jun. 30, 2014 Interest Rate SWAP Currently-Paying Contracts [Member] First Quarter 2015 [Member]	Jun. 30, 2014 Interest Rate SWAP Currently-Paying Contracts [Member] Second Quarter 2015 [Member]	Jun. 30, 2014 Interest Rate SWAP Currently-Paying Contracts [Member] Third Quarter 2015 [Member]	Jun. 30, 2014 Interest Rate SWAP Currently-Paying Contracts [Member] Fourth Quarter 2015 [Member]	Jun. 30, 2014 Interest Rate SWAP Currently-Paying Contracts [Member] First Quarter 2016 [Member]	Jun. 30, 2014 Interest Rate SWAP Currently-Paying Contracts [Member] Second quarter 2016 [Member]	Jun. 30, 2014 Interest Rate SWAP Forward-Starting Contracts [Member]	Jun. 30, 2014 Interest Rate SWAP Forward-Starting Contracts [Member] Fourth Quarter 2016 [Member]	Jun. 30, 2014 Interest Rate SWAP Forward-Starting Contracts [Member] Third Quarter 2016 [Member]	Dec. 31, 2010 Interest Rate Swap [Member]	Jun. 30, 2014 Interest Rate Swap [Member]	Dec. 31, 2013 Interest Rate Swap [Member]	Jun. 30, 2014 Interest Rate Swap New One [Member]	Jun. 30, 2014 Interest Rate Swap New One [Member]	Jun. 30, 2014 Interest Rate Swap New Two [Member]	Jun. 30, 2014 Interest Rate Swap New Two [Member]	Jun. 30, 2014 Interest Rate Swap Expired One [Member]	Jun. 30, 2014 Interest Rate Swap Expired One [Member]	Jun. 30, 2014 Repurchase Arrangements And Similar Borrowings [Member]	Dec. 31, 2013 Repurchase Arrangements And Similar Borrowings [Member]
Derivative Instruments And Hedging Activities [Line Items]
SWAP agreement notional amount during period														$ 100,000,000			$ 700,000,000	$ 1,400,000,000
SWAP agreement average interest rate during period (in hundredths)														4.09%			0.63%	0.57%
Swap agreement notional amount expiring during period																			1,100,000,000	2,800,000,000	400,000,000	600,000,000
SWAP agreement average interest rate expiring during period (in hundredths)																			0.47%	0.50%	0.51%	0.54%
Notional Amount	7,500,000,000	6,400,000,000	200,000,000	500,000,000	1,100,000,000	200,000,000	400,000,000	1,200,000,000	1,700,000,000	1,100,000,000	1,100,000,000	400,000,000	700,000,000
Average Fixed Rate Payment Requirement (in hundredths)		0.49%	0.51%	0.58%	0.50%	0.43%	0.47%	0.45%	0.51%	0.47%	0.59%	0.65%	0.56%
Payment term of LIBOR interest rate agreement														20 years			2 years
Derivative instruments unrealized losses to be recognized	19,000,000
Accrued Interest															$ 9,900,000	$ 5,500,000							$ 2,300,000	$ 4,700,000