Derivatives (Narrative) (Details) (USD $)	3 Months Ended
	Mar. 31, 2012		Mar. 31, 2011
Derivative Instruments, Gain (Loss) [Line Items]
Expected derivative maturity date	Dec. 01, 2013
Accumulated OCI gain (loss), net of tax	$ 13,503,000	[1]	$ 20,704,000	[1]
Expected earnings transfer	14,600,000
Period over which gain included in AOCI will be transferred to earnings, months	12
Interest Rate Swaps [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Accumulated OCI gain (loss), net of tax	$ 0	[1]	$ 840,000	[1]

[1] Net of taxes.