Condensed Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012
Operating activities
Net cash provided by operating activities	$ 57,975	$ 101,300
Investing activities
Purchases of securities available for sale	(106,521)	(83,426)
Proceeds from sales of securities available for sale	9,015	86,850
Proceeds from call/maturities of securities available for sale	42,898	74,681
Purchases of securities held to maturity	(70,075)	(69,564)
Proceeds from sales of securities held to maturity	4,459	0
Proceeds from call/maturities of securities held to maturity	34,670	111,391
Net increase in loans	(86,810)	(128,965)
Purchases of premises and equipment	(5,908)	(6,012)
Proceeds from sales of premises and equipment	0	45
Net cash used in investing activities	(178,272)	(15,000)
Financing activities
Net (decrease) increase in noninterest-bearing deposits	(7,249)	7,327
Net increase (decrease) in interest-bearing deposits	51,186	(13,368)
Net increase (decrease) in short-term borrowings	37,565	(3,785)
Repayment of long-term debt	(6,401)	(80,864)
Cash paid for dividends	(8,603)	(8,554)
Cash received on exercise of stock-based compensation	239	333
Excess tax benefit from stock-based compensation	155	0
Net cash provided by (used in) financing activities	66,892	(98,911)
Net decrease in cash and cash equivalents	(53,405)	(12,611)
Cash and cash equivalents at beginning of period	132,420	209,017
Cash and cash equivalents at end of period	79,015	196,406
Noncash transactions:
Transfers of loans to other real estate owned	$ 10,914	$ 21,999