Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Statement of Cash Flows [Abstract]
Net cash (used in) provided by operating activities	$ (5,884)	$ 10,331
Available-for-sale investment securities:
Purchases	(33,787)	(33,014)
Proceeds from sales	42,803	41,565
Proceeds from principal payments, calls and prepayments	21,646	15,642
Held-to-maturity investment securities:
Purchases	0	0
Proceeds from principal payments	316	312
Net decrease (increase) in loans	15,384	(29,981)
Net expenditures for premises and equipment	(2,152)	(1,674)
Proceeds from sales of other real estate owned	55	138
Proceeds from bank owned life insurance contracts	0	3,067
Business acquisitions, net of cash received	103,597	0
Return of investment in limited partnership and tax credit funds	0	358
Net cash provided by (used in) investing activities	147,862	(3,587)
Financing activities:
Net increase in non-interest-bearing deposits	76,533	7,738
Net (decrease) increase in interest-bearing deposits	(57,900)	44,601
Net increase (decrease) in short-term borrowings	2,824	(44,813)
Payments on long-term borrowings	(55,867)	(1,668)
Cash dividends paid	(2,149)	(1,517)
Purchase of treasury stock	(534)	(266)
Proceeds from issuance of common shares	0	2
Excess tax benefit from share-based payments	63	43
Net cash (used in) provided by financing activities	(37,030)	4,120
Net increase in cash and cash equivalents	104,948	10,864
Cash and cash equivalents at beginning of period	61,454	53,820
Cash and cash equivalents at end of period	$ 166,402	$ 64,684