Loans, Allowance for Loan and Lease Losses, and Reserve for Off-Balance Sheet Credit Commitments (Details 5) (USD $)	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012	Jul. 02, 2012	Jun. 30, 2012
Recorded Investment
With no related allowance recorded	$ 90,068,000	$ 102,783,000	$ 119,511,000
With an allowance recorded	33,767,000	48,154,000	19,081,000
Total impaired loans	123,835,000	150,937,000	138,592,000
Unpaid Contractual Principal Balance
With no related allowance recorded	120,360,000	135,358,000	162,309,000
With an allowance recorded	34,462,000	65,498,000	20,293,000
Total impaired loans	154,822,000	200,856,000	182,602,000
Related Allowance
Total impaired loans	2,884,000	14,118,000	2,403,000
Average Recorded Investment
With no related allowance recorded	104,790,000	101,221,000
With an allowance recorded	26,424,000	48,618,000
Total impaired loans	131,214,000	149,839,000
Interest Income Recognized
With no related allowance recorded	1,050,000	185,000
With an allowance recorded	427,000
Total impaired loans	1,477,000	185,000
Minimum limit for nonperforming loans to be individually evaluated for impairment				1,000,000	500,000
Minimum limit for measuring impairment at the relationship level for borrowers with multiple loans exceeding $1,000,000				1,000,000
Outstanding loan amount of previously reported impaired loans under $1,000,000	7,200,000
Commercial
Recorded Investment
With no related allowance recorded	19,066,000	27,822,000	18,761,000
With an allowance recorded	7,573,000	12,593,000	7,516,000
Total impaired loans	26,639,000	40,415,000	26,277,000
Unpaid Contractual Principal Balance
With no related allowance recorded	19,602,000	36,069,000	24,135,000
With an allowance recorded	7,608,000	17,643,000	8,038,000
Total impaired loans	27,210,000	53,712,000	32,173,000
Related Allowance
Total impaired loans	869,000	3,335,000	952,000
Average Recorded Investment
With no related allowance recorded	18,914,000	18,988,000
With an allowance recorded	7,544,000	14,110,000
Total impaired loans	26,458,000	33,098,000
Interest Income Recognized
With no related allowance recorded	419,000
With an allowance recorded	46,000
Total impaired loans	465,000
Commercial real estate mortgages
Recorded Investment
With no related allowance recorded	29,403,000	14,008,000	42,882,000
With an allowance recorded	13,344,000	8,298,000	10,203,000
Total impaired loans	42,747,000	22,306,000	53,085,000
Unpaid Contractual Principal Balance
With no related allowance recorded	34,927,000	19,022,000	49,110,000
With an allowance recorded	13,689,000	8,715,000	10,783,000
Total impaired loans	48,616,000	27,737,000	59,893,000
Related Allowance
Total impaired loans	1,148,000	1,019,000	1,326,000
Average Recorded Investment
With no related allowance recorded	36,142,000	16,938,000
With an allowance recorded	11,773,000	9,555,000
Total impaired loans	47,915,000	26,493,000
Interest Income Recognized
With no related allowance recorded	235,000	69,000
With an allowance recorded	168,000
Total impaired loans	403,000	69,000
Residential mortgage
Recorded Investment
With no related allowance recorded	7,963,000	9,233,000	8,347,000
With an allowance recorded		3,767,000	463,000
Total impaired loans	7,963,000	13,000,000	8,810,000
Unpaid Contractual Principal Balance
With no related allowance recorded	8,600,000	10,434,000	9,194,000
With an allowance recorded		3,843,000	507,000
Total impaired loans	8,600,000	14,277,000	9,701,000
Related Allowance
Total impaired loans		331,000	9,000
Average Recorded Investment
With no related allowance recorded	8,155,000	8,208,000
With an allowance recorded	232,000	2,866,000
Total impaired loans	8,387,000	11,074,000
Interest Income Recognized
With no related allowance recorded	32,000
Total impaired loans	32,000
Fixed
Recorded Investment
With no related allowance recorded	3,917,000	2,666,000	3,482,000
With an allowance recorded		2,341,000	463,000
Unpaid Contractual Principal Balance
With no related allowance recorded	4,246,000	3,194,000	3,757,000
With an allowance recorded		2,367,000	507,000
Related Allowance
Total impaired loans		287,000	9,000
Average Recorded Investment
With no related allowance recorded	3,699,000	3,080,000
With an allowance recorded	232,000	1,428,000
Interest Income Recognized
With no related allowance recorded	18,000
Variable
Recorded Investment
With no related allowance recorded	4,046,000	6,567,000	4,865,000
With an allowance recorded		1,426,000
Unpaid Contractual Principal Balance
With no related allowance recorded	4,354,000	7,240,000	5,437,000
With an allowance recorded		1,476,000
Related Allowance
Total impaired loans		44,000
Average Recorded Investment
With no related allowance recorded	4,456,000	5,128,000
With an allowance recorded		1,438,000
Interest Income Recognized
With no related allowance recorded	14,000
Real estate construction
Recorded Investment
With no related allowance recorded	31,496,000	45,135,000	45,510,000
With an allowance recorded	12,850,000	22,551,000
Total impaired loans	44,346,000	67,686,000	45,510,000
Unpaid Contractual Principal Balance
With no related allowance recorded	53,858,000	61,721,000	74,283,000
With an allowance recorded	13,165,000	34,312,000
Total impaired loans	67,023,000	96,033,000	74,283,000
Related Allowance
Total impaired loans	867,000	9,395,000
Average Recorded Investment
With no related allowance recorded	38,503,000	50,781,000
With an allowance recorded	6,425,000	20,968,000
Total impaired loans	44,928,000	71,749,000
Interest Income Recognized
With no related allowance recorded	364,000	116,000
With an allowance recorded	213,000
Total impaired loans	577,000	116,000
Construction
Recorded Investment
With no related allowance recorded	19,332,000	21,045,000	19,762,000
Unpaid Contractual Principal Balance
With no related allowance recorded	29,787,000	34,381,000	33,267,000
Average Recorded Investment
With no related allowance recorded	19,547,000	24,240,000
Interest Income Recognized
With no related allowance recorded	330,000	116,000
Land
Recorded Investment
With no related allowance recorded	12,164,000	24,090,000	25,748,000
With an allowance recorded	12,850,000	22,551,000
Unpaid Contractual Principal Balance
With no related allowance recorded	24,071,000	27,340,000	41,016,000
With an allowance recorded	13,165,000	34,312,000
Related Allowance
Total impaired loans	867,000	9,395,000
Average Recorded Investment
With no related allowance recorded	18,956,000	26,541,000
With an allowance recorded	6,425,000	20,968,000
Interest Income Recognized
With no related allowance recorded	34,000
With an allowance recorded	213,000
Home equity loans and lines of credit
Recorded Investment
With no related allowance recorded	2,140,000	6,035,000	3,562,000
With an allowance recorded		945,000	899,000
Total impaired loans	2,140,000	6,980,000	4,461,000
Unpaid Contractual Principal Balance
With no related allowance recorded	3,373,000	7,185,000	4,660,000
With an allowance recorded		985,000	965,000
Total impaired loans	3,373,000	8,170,000	5,625,000
Related Allowance
Total impaired loans		38,000	116,000
Average Recorded Investment
With no related allowance recorded	2,851,000	5,688,000
With an allowance recorded	450,000	1,119,000
Total impaired loans	3,301,000	6,807,000
Installment loan
Recorded Investment
With no related allowance recorded		550,000	449,000
Total impaired loans		550,000	449,000
Unpaid Contractual Principal Balance
With no related allowance recorded		927,000	927,000
Total impaired loans		927,000	927,000
Average Recorded Investment
With no related allowance recorded	225,000	604,000
Total impaired loans		604,000
Consumer Installment loan
Recorded Investment
With no related allowance recorded		550,000	449,000
Unpaid Contractual Principal Balance
With no related allowance recorded		927,000	927,000
Average Recorded Investment
With no related allowance recorded	225,000	604,000
Total impaired loans	225,000
Lease financing
Average Recorded Investment
With no related allowance recorded		14,000
Total impaired loans		$ 14,000