Shareholders' Equity And Earnings Per Share (Market Value Of Company Common Stock And Settlement Rate) (Detail) (USD $)	9 Months Ended
	Sep. 30, 2013
Applicable market value of Company common stock - Less than or equal to thirty dollars
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Settlement Rate, per share	1.6666
Applicable market value of Company common stock - Greater than thirty dollars but less than thirty seven point five zero dollars
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Settlement Rate, Market Value	50.00
Applicable market value of Company common stock - Greater than or equal to thirty seven point five zero dollars
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Settlement Rate, per share	1.3333
Minimum [Member]
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Settlement Rate, per share	1.3333
Minimum [Member] | Applicable market value of Company common stock - Less than or equal to thirty dollars
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Applicable market value of Company common stock	$ 30.00
Minimum [Member] | Applicable market value of Company common stock - Greater than thirty dollars but less than thirty seven point five zero dollars
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Applicable market value of Company common stock	$ 30.00
Minimum [Member] | Applicable market value of Company common stock - Greater than or equal to thirty seven point five zero dollars
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Settlement Rate, per share	1.3333
Maximum [Member]
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Settlement Rate, per share	1.6666
Maximum [Member] | Applicable market value of Company common stock - Less than or equal to thirty dollars
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Settlement Rate, per share	1.6666
Maximum [Member] | Applicable market value of Company common stock - Greater than thirty dollars but less than thirty seven point five zero dollars
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Applicable market value of Company common stock	$ 37.5
Maximum [Member] | Applicable market value of Company common stock - Greater than or equal to thirty seven point five zero dollars
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Applicable market value of Company common stock	$ 37.5