Derivative Financial Instruments (Fair Value Of Derivative Financial Instruments Designated As Cash Flow Hedges) (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Derivative [Line Items]
Notional Amount	$ 1,340,819	$ 1,403,512
Interest rate cap on FHLB advances [Member]
Derivative [Line Items]
Number of Instruments	2	0
Notional Amount	50,000	0
Cash Flow Hedge Derivative Instrument Assets at Fair Value	3,056	0
Interest rate swap on FHLB advances [Member]
Derivative [Line Items]
Number of Instruments	0	1
Notional Amount	0	100,000
Estimated Fair Value	0	(497)
Forward settle interest rate swap on anticipated debt [Member]
Derivative [Line Items]
Number of Instruments	0	4
Notional Amount	0	100,000
Estimated Fair Value	$ 0	$ (1,130)