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Allowance for Loan and Lease Losses and Unfunded Commitments and Letters of Credit (Allowance for Noncovered Loan and Lease Losses) (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2016 | Sep. 30, 2016 | Jun. 30, 2016 | Mar. 31, 2016 | Dec. 31, 2015 | Sep. 30, 2015 | Jun. 30, 2015 | Mar. 31, 2015 | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |  |  |  |  |  |  |
Balance at beginning of year |  |  |  | $ 68,172 |  |  |  | $ 69,569 | $ 68,172 | $ 69,569 | $ 72,454
Charge-offs |  |  |  |  |  |  |  |  | (21,462) | (25,067) | (24,722)
Recoveries |  |  |  |  |  |  |  |  | 12,555 | 15,079 | 15,110
Provision for loan and lease losses | $ 18 | $ 1,866 | $ 3,640 | 5,254 | $ 2,349 | $ 2,831 | $ 2,202 | 1,209 | 10,778 | 8,591 | 6,727
Balance at the end of year | 70,043 |  |  |  | 68,172 |  |  |  | 70,043 | 68,172 | 69,569
Specific Reserve | 761 |  |  |  | 653 |  |  |  | 761 | 653 | 241
General Allocation | 69,282 |  |  |  | 67,519 |  |  |  | 69,282 | 67,519 | 69,328
Consumer [Member] |  |  |  |  |  |  |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |  |  |  |  |  |  |
Balance at beginning of year |  |  |  | 3,531 |  |  |  | 3,180 | 3,531 | 3,180 | 2,547
Charge-offs |  |  |  |  |  |  |  |  | (1,238) | (2,066) | (2,774)
Recoveries |  |  |  |  |  |  |  |  | 933 | 931 | 1,353
Provision for loan and lease losses |  |  |  |  |  |  |  |  | 308 | 1,486 | 2,054
Balance at the end of year | 3,534 |  |  |  | 3,531 |  |  |  | 3,534 | 3,531 | 3,180
Specific Reserve | 57 |  |  |  | 15 |  |  |  | 57 | 15 | 0
General Allocation | 3,477 |  |  |  | 3,516 |  |  |  | 3,477 | 3,516 | 3,180
Purchased Credit Impaired Loans [Member] |  |  |  |  |  |  |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |  |  |  |  |  |  |
Balance at beginning of year |  |  |  | 13,726 |  |  |  | 16,336 | 13,726 | 16,336 | 20,174
Charge-offs |  |  |  |  |  |  |  |  | (9,944) | (13,854) | (14,436)
Recoveries |  |  |  |  |  |  |  |  | 7,004 | 7,329 | 7,721
Provision for loan and lease losses |  |  |  |  |  |  |  |  | (271) | 3,915 | 2,877
Balance at the end of year | 10,515 |  |  |  | 13,726 |  |  |  | 10,515 | 13,726 | 16,336
Specific Reserve | 0 |  |  |  | 0 |  |  |  | 0 | 0 | 0
General Allocation | 10,515 |  |  |  | 13,726 |  |  |  | 10,515 | 13,726 | 16,336
Unallocated Financing Receivables [Member] |  |  |  |  |  |  |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |  |  |  |  |  |  |
Balance at beginning of year |  |  |  | 569 |  |  |  | 1,844 | 569 | 1,844 | 1,655
Charge-offs |  |  |  |  |  |  |  |  | 0 | 0 | 0
Recoveries |  |  |  |  |  |  |  |  | 0 | 0 | 0
Provision for loan and lease losses |  |  |  |  |  |  |  |  | (343) | (1,275) | 189
Balance at the end of year | 226 |  |  |  | 569 |  |  |  | 226 | 569 | 1,844
Specific Reserve | 0 |  |  |  | 0 |  |  |  | 0 | 0 | 0
General Allocation | 226 |  |  |  | 569 |  |  |  | 226 | 569 | 1,844
Commercial business: Secured loans [Member] |  |  |  |  |  |  |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |  |  |  |  |  |  |
Balance at beginning of year |  |  |  | 32,321 |  |  |  | 25,923 | 32,321 | 25,923 | 31,027
Charge-offs |  |  |  |  |  |  |  |  | (9,993) | (7,486) | (4,159)
Recoveries |  |  |  |  |  |  |  |  | 2,483 | 2,069 | 2,637
Provision for loan and lease losses |  |  |  |  |  |  |  |  | 11,239 | 11,815 | (3,582)
Balance at the end of year | 36,050 |  |  |  | 32,321 |  |  |  | 36,050 | 32,321 | 25,923
Specific Reserve | 664 |  |  |  | 321 |  |  |  | 664 | 321 | 25
General Allocation | 35,386 |  |  |  | 32,000 |  |  |  | 35,386 | 32,000 | 25,898
Commercial business: Unsecured loans [Member] |  |  |  |  |  |  |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |  |  |  |  |  |  |
Balance at beginning of year |  |  |  | 1,299 |  |  |  | 927 | 1,299 | 927 | 696
Charge-offs |  |  |  |  |  |  |  |  | (75) | (780) | (130)
Recoveries |  |  |  |  |  |  |  |  | 162 | 267 | 370
Provision for loan and lease losses |  |  |  |  |  |  |  |  | (426) | 885 | (9)
Balance at the end of year | 960 |  |  |  | 1,299 |  |  |  | 960 | 1,299 | 927
Specific Reserve | 0 |  |  |  | 0 |  |  |  | 0 | 0 | 2
General Allocation | 960 |  |  |  | 1,299 |  |  |  | 960 | 1,299 | 925
Real estate: One-to-four family residential [Member] |  |  |  |  |  |  |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |  |  |  |  |  |  |
Balance at beginning of year |  |  |  | 916 |  |  |  | 2,281 | 916 | 2,281 | 1,252
Charge-offs |  |  |  |  |  |  |  |  | (35) | (376) | (230)
Recoveries |  |  |  |  |  |  |  |  | 171 | 307 | 159
Provision for loan and lease losses |  |  |  |  |  |  |  |  | (453) | (1,296) | 1,100
Balance at the end of year | 599 |  |  |  | 916 |  |  |  | 599 | 916 | 2,281
Specific Reserve | 12 |  |  |  | 314 |  |  |  | 12 | 314 | 120
General Allocation | 587 |  |  |  | 602 |  |  |  | 587 | 602 | 2,161
Real estate: Commercial and multifamily residential: Commercial land [Member] |  |  |  |  |  |  |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |  |  |  |  |  |  |
Balance at beginning of year |  |  |  | 1,178 |  |  |  | 799 | 1,178 | 799 | 489
Charge-offs |  |  |  |  |  |  |  |  | (26) | 0 | (29)
Recoveries |  |  |  |  |  |  |  |  | 2 | 291 | 70
Provision for loan and lease losses |  |  |  |  |  |  |  |  | 643 | 88 | 269
Balance at the end of year | 1,797 |  |  |  | 1,178 |  |  |  | 1,797 | 1,178 | 799
Specific Reserve | 0 |  |  |  | 0 |  |  |  | 0 | 0 | 0
General Allocation | 1,797 |  |  |  | 1,178 |  |  |  | 1,797 | 1,178 | 799
Real estate: Commercial and multifamiIy residential: Income property [Member] |  |  |  |  |  |  |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |  |  |  |  |  |  |
Balance at beginning of year |  |  |  | 6,616 |  |  |  | 9,159 | 6,616 | 9,159 | 9,234
Charge-offs |  |  |  |  |  |  |  |  | 0 | (390) | (1,934)
Recoveries |  |  |  |  |  |  |  |  | 966 | 3,568 | 819
Provision for loan and lease losses |  |  |  |  |  |  |  |  | (240) | (5,721) | 1,040
Balance at the end of year | 7,342 |  |  |  | 6,616 |  |  |  | 7,342 | 6,616 | 9,159
Specific Reserve | 27 |  |  |  | 0 |  |  |  | 27 | 0 | 0
General Allocation | 7,315 |  |  |  | 6,616 |  |  |  | 7,315 | 6,616 | 9,159
Real estate: Commercial and multifamiIy residential: Owner occupied [Member] |  |  |  |  |  |  |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |  |  |  |  |  |  |
Balance at beginning of year |  |  |  | 5,550 |  |  |  | 5,007 | 5,550 | 5,007 | 3,605
Charge-offs |  |  |  |  |  |  |  |  | (63) | (115) | (1,030)
Recoveries |  |  |  |  |  |  |  |  | 434 | 116 | 51
Provision for loan and lease losses |  |  |  |  |  |  |  |  | 518 | 542 | 2,381
Balance at the end of year | 6,439 |  |  |  | 5,550 |  |  |  | 6,439 | 5,550 | 5,007
Specific Reserve | 0 |  |  |  | 0 |  |  |  | 0 | 0 | 27
General Allocation | 6,439 |  |  |  | 5,550 |  |  |  | 6,439 | 5,550 | 4,980
Real estate construction: One-to-four family residential: Land and acquisition [Member] |  |  |  |  |  |  |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |  |  |  |  |  |  |
Balance at beginning of year |  |  |  | 339 |  |  |  | 1,197 | 339 | 1,197 | 610
Charge-offs |  |  |  |  |  |  |  |  | (88) | 0 | 0
Recoveries |  |  |  |  |  |  |  |  | 57 | 103 | 740
Provision for loan and lease losses |  |  |  |  |  |  |  |  | 8 | (961) | (153)
Balance at the end of year | 316 |  |  |  | 339 |  |  |  | 316 | 339 | 1,197
Specific Reserve | 1 |  |  |  | 0 |  |  |  | 1 | 0 | 67
General Allocation | 315 |  |  |  | 339 |  |  |  | 315 | 339 | 1,130
Real estate construction: One-to-four family residential: Residential construction [Member] |  |  |  |  |  |  |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |  |  |  |  |  |  |
Balance at beginning of year |  |  |  | 733 |  |  |  | 1,860 | 733 | 1,860 | 822
Charge-offs |  |  |  |  |  |  |  |  | 0 | 0 | 0
Recoveries |  |  |  |  |  |  |  |  | 234 | 90 | 1,190
Provision for loan and lease losses |  |  |  |  |  |  |  |  | (298) | (1,217) | (152)
Balance at the end of year | 669 |  |  |  | 733 |  |  |  | 669 | 733 | 1,860
Specific Reserve | 0 |  |  |  | 3 |  |  |  | 0 | 3 | 0
General Allocation | 669 |  |  |  | 730 |  |  |  | 669 | 730 | 1,860
Real estate construction: Commercial and multifamily residential: Income property [Member] |  |  |  |  |  |  |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |  |  |  |  |  |  |
Balance at beginning of year |  |  |  | 388 |  |  |  | 622 | 388 | 622 | 285
Charge-offs |  |  |  |  |  |  |  |  | 0 | 0 | 0
Recoveries |  |  |  |  |  |  |  |  | 109 | 8 | 0
Provision for loan and lease losses |  |  |  |  |  |  |  |  | (93) | (242) | 337
Balance at the end of year | 404 |  |  |  | 388 |  |  |  | 404 | 388 | 622
Specific Reserve | 0 |  |  |  | 0 |  |  |  | 0 | 0 | 0
General Allocation | 404 |  |  |  | 388 |  |  |  | 404 | 388 | 622
Real estate construction: Commercial and multifamily residential: Owner occupied [Member] |  |  |  |  |  |  |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |  |  |  |  |  |  |
Balance at beginning of year |  |  |  | $ 1,006 |  |  |  | $ 434 | 1,006 | 434 | 58
Charge-offs |  |  |  |  |  |  |  |  | 0 | 0 | 0
Recoveries |  |  |  |  |  |  |  |  | 0 | 0 | 0
Provision for loan and lease losses |  |  |  |  |  |  |  |  | 186 | 572 | 376
Balance at the end of year | 1,192 |  |  |  | 1,006 |  |  |  | 1,192 | 1,006 | 434
Specific Reserve | 0 |  |  |  | 0 |  |  |  | 0 | 0 | 0
General Allocation | $ 1,192 |  |  |  | $ 1,006 |  |  |  | $ 1,192 | $ 1,006 | $ 434

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