Earnings Per Common Share (Earnings Per Share Basic And Diluted) (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Earnings Per Share Basic And Diluted By Common Class [Line Items]
Net income from continuing operations available to common shareholders									$ 168,746	$ 171,237	$ 146,098
Less: Dividends to participating shares									(179)	(134)	(70)
Income allocated to participating shares									(438)	(614)	(666)
Net income allocated to common shareholders									168,129	170,489	145,362
Net income from discontinued operations available to common shareholders									$ 0	$ 0	$ 1,995
Weighted average common shares outstanding - basic									88,713	87,211	87,007
Stock options and restricted stock (in shares)									436	281	368
Weighted average common shares outstanding - diluted									90,261	91,649	91,688
Earnings from continuing operations per common share, Basic (in dollars per share)									$ 1.90	$ 1.96	$ 1.67
Earnings from continuing operations per common share, Diluted (in dollars per share)									$ 1.86	$ 1.86	$ 1.59
Earnings from discontinued operations per common share, Basic (in dollars per share)									$ 0.00	$ 0.00	$ 0.02
Earnings from discontinued operations per common share, Diluted (in dollars per share)									$ 0.00	$ 0.00	$ 0.02
Net income available to common shareholders per common share, Basic (in dollars per share)	$ 0.46	$ 0.50	$ 0.49	$ 0.46	$ 0.55	$ 0.51	$ 0.46	$ 0.44	$ 1.90	$ 1.96	$ 1.69
Net income available to common shareholders per common share, Diluted (in dollars per share)	$ 0.45	$ 0.49	$ 0.48	$ 0.44	$ 0.52	$ 0.48	$ 0.44	$ 0.42	$ 1.86	$ 1.86	$ 1.61
Warrants - Series A1 And A2 [Member]
Earnings Per Share Basic And Diluted By Common Class [Line Items]
Warrants (in shares)									922	4,048	4,147
Warrants - Other [Member]
Earnings Per Share Basic And Diluted By Common Class [Line Items]
Warrants (in shares)									190	109	166