Other Noninterest Income - Components of Other Income (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Income Statement [Abstract]
Income from bank owned life insurance	$ 2,574	$ 2,870	$ 8,764	$ 8,617
Credit related fees	2,995	1,545	5,969	5,130
Income from derivatives	1,257	455	3,296	2,091
Safety deposit box income	467	502	1,480	1,524
Gain/(loss) on sale of assets	801	2,705	1,277	2,909
Other miscellaneous	1,432	1,693	5,863	10,830
Total other noninterest income	$ 9,526	$ 9,770	$ 26,649	$ 31,101