CONSOLIDATED STATEMENTS OF INCOME (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Interest income:
Loans receivable	$ 287,289	$ 308,254	$ 320,100
Mortgage-backed securities	12,818	16,738	23,450
Taxable investment securities	4,021	2,328	2,452
Tax-free investment securities	7,817	9,119	11,514
Interest-earning deposits	1,093	1,599	1,712
Total interest income	313,038	338,038	359,228
Interest expense:
Deposits	29,279	43,377	60,721
Borrowed funds	31,883	31,822	32,080
Total interest expense	61,162	75,199	92,801
Net interest income	251,876	262,839	266,427
Provision for loan losses	18,519	26,338	34,170
Net interest income after provision for loan losses	233,357	236,501	232,257
Noninterest income:
Impairment losses on securities	(713)	(996)	(2,081)
Noncredit related losses on securities not expected to be sold (recognized in other comprehensive income)		665	1,144
Net impairment losses	(713)	(331)	(937)
Gain on sale of investments, net	6,118	654	358
Service charges and fees	35,884	35,623	36,220
Trust and other financial services income	9,330	8,544	8,125
Insurance commission income	8,635	6,264	6,548
Loss on real estate owned, net	(3,186)	(5,643)	(2,426)
Income from bank owned life insurance	5,197	4,961	6,019
Mortgage banking income	1,623	4,678	858
Other operating income	3,959	4,154	4,213
Total noninterest income	66,847	58,904	58,978
Noninterest expense:
Compensation and employee benefits	112,190	111,727	106,595
Premises and occupancy costs	23,182	22,409	23,055
Office operations	14,454	13,224	12,850
Processing expenses	25,548	25,000	23,332
Professional services	6,267	7,005	5,224
Amortization of other intangible assets	1,210	1,012	1,819
Marketing expenses	6,284	7,829	9,953
Real estate owned expense	2,437	2,620	1,625
Federal deposit insurance premiums	5,600	5,554	7,101
Other expenses	9,962	9,097	8,673
Total noninterest expense	207,134	205,477	200,227
Income before income taxes	93,070	89,928	91,008
Provision for income taxes:
Federal	23,276	22,484	22,623
State	3,055	3,884	4,234
Total provision for income taxes	26,331	26,368	26,857
Net income	$ 66,739	$ 63,560	$ 64,151
Basic earnings per share (in dollars per share)	$ 0.74	$ 0.68	$ 0.64
Diluted earnings per share (in dollars per share)	$ 0.73	$ 0.68	$ 0.64