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Loan and Lease Receivables, Impaired Loans and Leases and Allowance for Loan and Lease Losses (Impaired Loans and Leases) (Details) - USD ($) $ in Thousands | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2017 | Dec. 31, 2016
Recorded Investment |  |  |
With no impairment reserve recorded |  | $ 17,972 | $ 11,345
With impairment reserve recorded |  | 15,535 | 14,566
Total |  | 33,507 | 25,911
Unpaid Principal Balance |  |  |
With no impairment reserve recorded |  | 21,967 | 14,722
With impairment reserve recorded |  | 16,008 | 14,572
Total |  | 37,975 | 29,294
Impairment Reserve |  |  |
Impairment Reserve |  | 5,790 | 5,599
Average Recorded Investment(1) |  |  |
With no impairment reserve recorded | [1] | 20,232 | 13,371
With impairment reserve recorded | [1] | 14,639 | 9,615
Total | [1] | 34,871 | 22,986
Foregone Interest Income |  |  |
With no impairment reserve recorded |  | 1,389 | 838
With impairment reserve recorded |  | 580 | 779
Foregone interest income |  | 1,969 | 1,617
Interest Income Recognized |  |  |
With no impairment reserve recorded |  | 0 | 614
With impairment reserve recorded |  | 0 | 0
Total |  | 0 | 614
Net Foregone Interest Income |  |  |
With no impairment reserve recorded |  | 1,389 | 224
With impairment reserve recorded |  | 580 | 779
Total |  | 1,969 | 1,003
Commercial real estate — owner occupied |  |  |
Recorded Investment |  |  |
With no impairment reserve recorded |  | 6,727 | 1,788
With impairment reserve recorded |  | 411 | 499
Total |  | 7,138 | 2,287
Unpaid Principal Balance |  |  |
With no impairment reserve recorded |  | 6,727 | 1,788
With impairment reserve recorded |  | 411 | 499
Total |  | 7,138 | 2,287
Impairment Reserve |  |  |
Impairment Reserve |  | 15 | 70
Average Recorded Investment(1) |  |  |
With no impairment reserve recorded | [1] | 4,898 | 3,577
With impairment reserve recorded | [1] | 424 | 111
Total | [1] | 5,322 | 3,688
Foregone Interest Income |  |  |
With no impairment reserve recorded |  | 394 | 328
With impairment reserve recorded |  | 19 | 28
Foregone interest income |  | 413 | 356
Interest Income Recognized |  |  |
With no impairment reserve recorded |  | 0 | 118
With impairment reserve recorded |  | 0 | 0
Total |  | 0 | 118
Net Foregone Interest Income |  |  |
With no impairment reserve recorded |  | 394 | 210
With impairment reserve recorded |  | 19 | 28
Total |  | 413 | 238
Commercial real estate — non-owner occupied |  |  |
Recorded Investment |  |  |
With no impairment reserve recorded |  | 1,826 | 1,609
With impairment reserve recorded |  | 0 | 0
Total |  | 1,826 | 1,609
Unpaid Principal Balance |  |  |
With no impairment reserve recorded |  | 1,866 | 1,647
With impairment reserve recorded |  | 0 | 0
Total |  | 1,866 | 1,647
Impairment Reserve |  |  |
Impairment Reserve |  | 0 | 0
Average Recorded Investment(1) |  |  |
With no impairment reserve recorded | [1] | 1,932 | 1,318
With impairment reserve recorded | [1] | 0 | 0
Total | [1] | 1,932 | 1,318
Foregone Interest Income |  |  |
With no impairment reserve recorded |  | 99 | 91
With impairment reserve recorded |  | 0 | 0
Foregone interest income |  | 99 | 91
Interest Income Recognized |  |  |
With no impairment reserve recorded |  | 0 | 79
With impairment reserve recorded |  | 0 | 0
Total |  | 0 | 79
Net Foregone Interest Income |  |  |
With no impairment reserve recorded |  | 99 | 12
With impairment reserve recorded |  | 0 | 0
Total |  | 99 | 12
Land development |  |  |
Recorded Investment |  |  |
With no impairment reserve recorded |  | 2,770 | 3,440
With impairment reserve recorded |  | 0 | 0
Total |  | 2,770 | 3,440
Unpaid Principal Balance |  |  |
With no impairment reserve recorded |  | 5,441 | 6,111
With impairment reserve recorded |  | 0 | 0
Total |  | 5,441 | 6,111
Impairment Reserve |  |  |
Impairment Reserve |  | 0 | 0
Average Recorded Investment(1) |  |  |
With no impairment reserve recorded | [1] | 3,218 | 3,898
With impairment reserve recorded | [1] | 0 | 0
Total | [1] | 3,218 | 3,898
Foregone Interest Income |  |  |
With no impairment reserve recorded |  | 65 | 107
With impairment reserve recorded |  | 0 | 0
Foregone interest income |  | 65 | 107
Interest Income Recognized |  |  |
With no impairment reserve recorded |  | 0 | 0
With impairment reserve recorded |  | 0 | 0
Total |  | 0 | 0
Net Foregone Interest Income |  |  |
With no impairment reserve recorded |  | 65 | 107
With impairment reserve recorded |  | 0 | 0
Total |  | 65 | 107
Construction |  |  |
Recorded Investment |  |  |
With no impairment reserve recorded |  | 2,482 | 436
With impairment reserve recorded |  | 2,872 | 2,482
Total |  | 5,354 | 2,918
Unpaid Principal Balance |  |  |
With no impairment reserve recorded |  | 2,482 | 438
With impairment reserve recorded |  | 2,872 | 2,482
Total |  | 5,354 | 2,920
Impairment Reserve |  |  |
Impairment Reserve |  | 94 | 1,790
Average Recorded Investment(1) |  |  |
With no impairment reserve recorded | [1] | 611 | 291
With impairment reserve recorded | [1] | 4,091 | 834
Total | [1] | 4,702 | 1,125
Foregone Interest Income |  |  |
With no impairment reserve recorded |  | 208 | 20
With impairment reserve recorded |  | 108 | 45
Foregone interest income |  | 316 | 65
Interest Income Recognized |  |  |
With no impairment reserve recorded |  | 0 | 0
With impairment reserve recorded |  | 0 | 0
Total |  | 0 | 0
Net Foregone Interest Income |  |  |
With no impairment reserve recorded |  | 208 | 20
With impairment reserve recorded |  | 108 | 45
Total |  | 316 | 65
Multi-family |  |  |
Recorded Investment |  |  |
With no impairment reserve recorded |  | 0 | 0
With impairment reserve recorded |  | 0 | 0
Total |  | 0 | 0
Unpaid Principal Balance |  |  |
With no impairment reserve recorded |  | 0 | 0
With impairment reserve recorded |  | 0 | 0
Total |  | 0 | 0
Impairment Reserve |  |  |
Impairment Reserve |  | 0 | 0
Average Recorded Investment(1) |  |  |
With no impairment reserve recorded | [1] | 1 | 0
With impairment reserve recorded | [1] | 0 | 0
Total | [1] | 1 | 0
Foregone Interest Income |  |  |
With no impairment reserve recorded |  | 0 | 1
With impairment reserve recorded |  | 0 | 0
Foregone interest income |  | 0 | 1
Interest Income Recognized |  |  |
With no impairment reserve recorded |  | 0 | 134
With impairment reserve recorded |  | 0 | 0
Total |  | 0 | 134
Net Foregone Interest Income |  |  |
With no impairment reserve recorded |  | 0 | (133)
With impairment reserve recorded |  | 0 | 0
Total |  | 0 | (133)
1-4 family |  |  |
Recorded Investment |  |  |
With no impairment reserve recorded |  | 2,065 | 2,379
With impairment reserve recorded |  | 0 | 193
Total |  | 2,065 | 2,572
Unpaid Principal Balance |  |  |
With no impairment reserve recorded |  | 2,319 | 2,379
With impairment reserve recorded |  | 0 | 199
Total |  | 2,319 | 2,578
Impairment Reserve |  |  |
Impairment Reserve |  | 0 | 39
Average Recorded Investment(1) |  |  |
With no impairment reserve recorded | [1] | 2,387 | 2,755
With impairment reserve recorded | [1] | 0 | 203
Total | [1] | 2,387 | 2,958
Foregone Interest Income |  |  |
With no impairment reserve recorded |  | 69 | 125
With impairment reserve recorded |  | 0 | 5
Foregone interest income |  | 69 | 130
Interest Income Recognized |  |  |
With no impairment reserve recorded |  | 0 | 94
With impairment reserve recorded |  | 0 | 0
Total |  | 0 | 94
Net Foregone Interest Income |  |  |
With no impairment reserve recorded |  | 69 | 31
With impairment reserve recorded |  | 0 | 5
Total |  | 69 | 36
Commercial and industrial |  |  |
Recorded Investment |  |  |
With no impairment reserve recorded |  | 1,740 | 1,307
With impairment reserve recorded |  | 12,229 | 11,166
Total |  | 13,969 | 12,473
Unpaid Principal Balance |  |  |
With no impairment reserve recorded |  | 2,103 | 1,307
With impairment reserve recorded |  | 12,702 | 11,166
Total |  | 14,805 | 12,473
Impairment Reserve |  |  |
Impairment Reserve |  | 5,658 | 3,700
Average Recorded Investment(1) |  |  |
With no impairment reserve recorded | [1] | 6,782 | 709
With impairment reserve recorded | [1] | 10,114 | 8,448
Total | [1] | 16,896 | 9,157
Foregone Interest Income |  |  |
With no impairment reserve recorded |  | 509 | 79
With impairment reserve recorded |  | 453 | 701
Foregone interest income |  | 962 | 780
Interest Income Recognized |  |  |
With no impairment reserve recorded |  | 0 | 62
With impairment reserve recorded |  | 0 | 0
Total |  | 0 | 62
Net Foregone Interest Income |  |  |
With no impairment reserve recorded |  | 509 | 17
With impairment reserve recorded |  | 453 | 701
Total |  | 962 | 718
Direct financing leases, net |  |  |
Recorded Investment |  |  |
With no impairment reserve recorded |  | 0 | 0
With impairment reserve recorded |  | 0 | 0
Total |  | 0 | 0
Unpaid Principal Balance |  |  |
With no impairment reserve recorded |  | 0 | 0
With impairment reserve recorded |  | 0 | 0
Total |  | 0 | 0
Impairment Reserve |  |  |
Impairment Reserve |  | 0 | 0
Average Recorded Investment(1) |  |  |
With no impairment reserve recorded | [1] | 0 | 6
With impairment reserve recorded | [1] | 0 | 0
Total | [1] | 0 | 6
Foregone Interest Income |  |  |
With no impairment reserve recorded |  | 0 | 0
With impairment reserve recorded |  | 0 | 0
Foregone interest income |  | 0 | 0
Interest Income Recognized |  |  |
With no impairment reserve recorded |  | 0 | 0
With impairment reserve recorded |  | 0 | 0
Total |  | 0 | 0
Net Foregone Interest Income |  |  |
With no impairment reserve recorded |  | 0 | 0
With impairment reserve recorded |  | 0 | 0
Total |  | 0 | 0
Home equity and second mortgages |  |  |
Recorded Investment |  |  |
With no impairment reserve recorded |  | 4 | 8
With impairment reserve recorded |  | 0 | 0
Total |  | 4 | 8
Unpaid Principal Balance |  |  |
With no impairment reserve recorded |  | 4 | 8
With impairment reserve recorded |  | 0 | 0
Total |  | 4 | 8
Impairment Reserve |  |  |
Impairment Reserve |  | 0 | 0
Average Recorded Investment(1) |  |  |
With no impairment reserve recorded | [1] | 6 | 307
With impairment reserve recorded | [1] | 0 | 0
Total | [1] | 6 | 307
Foregone Interest Income |  |  |
With no impairment reserve recorded |  | 0 | 16
With impairment reserve recorded |  | 0 | 0
Foregone interest income |  | 0 | 16
Interest Income Recognized |  |  |
With no impairment reserve recorded |  | 0 | 127
With impairment reserve recorded |  | 0 | 0
Total |  | 0 | 127
Net Foregone Interest Income |  |  |
With no impairment reserve recorded |  | 0 | (111)
With impairment reserve recorded |  | 0 | 0
Total |  | 0 | (111)
Other |  |  |
Recorded Investment |  |  |
With no impairment reserve recorded |  | 358 | 378
With impairment reserve recorded |  | 23 | 226
Total |  | 381 | 604
Unpaid Principal Balance |  |  |
With no impairment reserve recorded |  | 1,025 | 1,044
With impairment reserve recorded |  | 23 | 226
Total |  | 1,048 | 1,270
Impairment Reserve |  |  |
Impairment Reserve |  | 23 | 0
Average Recorded Investment(1) |  |  |
With no impairment reserve recorded | [1] | 397 | 510
With impairment reserve recorded | [1] | 10 | 19
Total | [1] | 407 | 529
Foregone Interest Income |  |  |
With no impairment reserve recorded |  | 45 | 71
With impairment reserve recorded |  | 0 | 0
Foregone interest income |  | 45 | 71
Interest Income Recognized |  |  |
With no impairment reserve recorded |  | 0 | 0
With impairment reserve recorded |  | 0 | 0
Total |  | 0 | 0
Net Foregone Interest Income |  |  |
With no impairment reserve recorded |  | 45 | 71
With impairment reserve recorded |  | 0 | 0
Total |  | $ 45 | $ 71
[1] | (1)Average recorded investment is calculated primarily using daily average balances.

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