Other Noninterest Income - Components of Other Income (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Income Statement [Abstract]
Income from bank owned life insurance	$ 2,314	$ 3,299
Credit related fees	2,732	1,441
Income from derivatives	759	631
Gain on sale of assets	1,682	314
Safety deposit box income	513	551
Other miscellaneous	2,427	2,232
Total noninterest income	$ 10,427	$ 8,468