Significant Transactions - Additional Information (Detail) $ / shares in Units, $ in Thousands							1 Months Ended		3 Months Ended								9 Months Ended	12 Months Ended				21 Months Ended
	Sep. 25, 2015 USD ($)	May. 15, 2015 USD ($)	Dec. 19, 2014 USD ($) parking_stall	Oct. 02, 2013 USD ($) $ / shares shares	Aug. 12, 2013 USD ($)	Jan. 30, 2009 USD ($) $ / shares shares	Jan. 31, 2015 USD ($)	Oct. 31, 2014 USD ($) $ / shares shares	Dec. 31, 2015 USD ($) $ / shares shares	Sep. 30, 2015 USD ($) Employee Branch	Jun. 30, 2015 USD ($)	Mar. 31, 2015 USD ($)	Dec. 31, 2014 USD ($) $ / shares shares	Sep. 30, 2014 USD ($)	Jun. 30, 2014 USD ($)	Mar. 31, 2014 USD ($)	Dec. 31, 2013 USD ($) shares	Dec. 31, 2015 USD ($) $ / shares shares	Dec. 31, 2014 USD ($) $ / shares shares	Dec. 31, 2013 USD ($)	Mar. 31, 2009 USD ($)	Dec. 31, 2013 USD ($)	Sep. 25, 2013 $ / shares shares	Sep. 19, 2013 $ / shares
Unusual Risk or Uncertainty [Line Items]
Number of stall parking ramp (in parking stalls) | parking_stall			261
Gain sale of properties			$ 1,400														$ 0	$ 0	$ 6,392
Deferred gain on sale leaseback													$ 6,400						6,400
Gain (loss) from the sale of branch operation																	0	986	991
Recorded gain from the sale of the branch																	(3)	1,676	1,328
Building acquired, purchase price							$ 4,000
Anticipated annual net cost saving										$ 5,400
Number of employees eligible for voluntary separation plan (in employee) | Employee										140
Number of bank employees (in employee) | Employee										705
Number of employees accepting Voluntary Separation Plan (in employee) | Employee										78
Number of retail branches closed | Branch										6
Number of positions expected to be eliminated (in employee) | Employee										21
Restructuring and related cost, one-time expected cost										$ 3,800
Valuation allowance									$ 4,200				113,099				94,800	4,200	113,099	$ 94,800		$ 94,800
Increase (decrease) in valuation allowance																	7,906	(108,899)	(5,806)
Provision for loan losses									$ (5,086)	(22,410)	$ (646)	$ (1,354)	$ (3,281)	$ (1,304)	$ 0	$ 0	275	(29,496)	(4,585)	$ 950
Payment for stock issue expenses																	0	$ 0	$ 2,324
Common shares, outstanding | shares									9,597,392				9,547,587					9,597,392	9,547,587
Other borrowings									$ 12,562				$ 13,752					$ 12,562	$ 13,752
Common stock, shares authorized | shares									11,900,000				11,900,000					11,900,000	11,900,000				2,000,000,000
Common stock, par value | $ / shares									$ 0.01				$ 0.01					$ 0.01	$ 0.01				$ 0.01	$ 0.10
Preferred stock, shares authorized | shares									100,000				100,000					100,000	100,000				1,000,000
Preferred stock, par value | $ / shares									$ 0.01				$ 0.01					$ 0.01	$ 0.01				$ 0.01
Number of Common stock under purchase agreement | shares									9,608,957				9,552,094					9,608,957	9,552,094
Treasury shares issued and sold | shares									11,565				4,507					11,565	4,507
Preferred stock exchanged for common stock																	0
Obligations under senior debt settlement agreement					$ 183,500
Payment under senior debt settlement agreement					49,000
Gain on extinguishment of debt					$ 134,500												134,514	$ 0	$ 0
Reorganization costs																	$ 1,929	0	$ (64)
Common Stock
Unusual Risk or Uncertainty [Line Items]
Common stock, shares issued | shares																	9,050,000		305,794
Shares authorized in relation with reverse stock split | shares				11,900,000
Reverse stock split, Par value | $ / shares				$ 0.01
Preferred stock exchanged for common stock																	$ (3)
Preferred Stock
Unusual Risk or Uncertainty [Line Items]
Shares authorized in relation with reverse stock split | shares				100,000
Reverse stock split, Par value | $ / shares				$ 0.01
Preferred stock exchanged for common stock																	110,000
Retained Earnings (Deficit)
Unusual Risk or Uncertainty [Line Items]
Preferred stock exchanged for common stock																	$ (104,000)
Troubled Assets Relief Program
Unusual Risk or Uncertainty [Line Items]
Proceeds from issuance of senior preferred shares																					$ 110,000
Common stock, par value | $ / shares						$ 0.10
Number of shares issued , reverse stock split | shares						300,000
Preferred stock liquidation preference value						$ 110,000
Warrants to purchase company common stock | shares						7,399,103
Stock redeemed or called during period issued to US Treasury value per share exercise price | $ / shares						$ 2.23
Number of preferred stock shares exchanged for common stock shares | shares						60,000,000
Income (loss) available to common stockholders basic and diluted						$ 104,000
Proceeds from sale of treasury stock																						$ 6,000
Troubled Assets Relief Program | Retained Earnings (Deficit)
Unusual Risk or Uncertainty [Line Items]
Preferred stock exchanged for common stock						$ 104,000
Troubled Assets Relief Program | Series B Cumulative Preferred Stock
Unusual Risk or Uncertainty [Line Items]
Treasury shares issued and sold | shares						110,000
Line of Credit
Unusual Risk or Uncertainty [Line Items]
Other borrowings																					$ 183,500
Credit agreement
Unusual Risk or Uncertainty [Line Items]
Reorganization costs																		2,200,000
Liabilities subject to compromise									$ 188,300									188,300
Outstanding Credit Agreement included in liabilities subject to compromise									116,300									116,300
Interest due under the Credit Agreement																		67,200
Expense recognized in other liabilities									$ 4,800									4,800
IPO
Unusual Risk or Uncertainty [Line Items]
Common stock, shares issued | shares								250,000
Common stock, issued price per share | $ / shares								$ 26.00
IPO | Underwriting Discounts and Commissions
Unusual Risk or Uncertainty [Line Items]
Payment for stock issue expenses								$ 517
IPO | Other Offering Expenses
Unusual Risk or Uncertainty [Line Items]
Payment for stock issue expenses								$ 1,800
Over-Allotment Option
Unusual Risk or Uncertainty [Line Items]
Common stock, shares issued | shares								55,794
Underwriters over-allotments option exercise period								30 days
Net proceeds from IPO including proceeds from over allotment								$ 5,600
Common shares, outstanding | shares								9,597,392
Private Placement
Unusual Risk or Uncertainty [Line Items]
Common stock, par value | $ / shares				$ 0.10
Number of Common stock under purchase agreement | shares				1,750,000,000
Number of shares issued , reverse stock split | shares				8,750,000
Purchase price per share | $ / shares				$ 20.00
Proceeds from private placements				$ 175,000
Transaction costs incurred				$ 14,400
Richard Center
Unusual Risk or Uncertainty [Line Items]
Gain sale of properties																		1,000
Deposits assets sold																		16,600
Viroqua Branch
Unusual Risk or Uncertainty [Line Items]
Deposits assets sold		$ 11,200
Gain (loss) from the sale of branch operation		$ 448
Winneconne Branch
Unusual Risk or Uncertainty [Line Items]
Deposits assets sold	$ 11,900
Gain (loss) from the sale of branch operation	538
Recorded gain from the sale of the branch	$ 294
Appleton Branch
Unusual Risk or Uncertainty [Line Items]
Recorded gain from the sale of the branch										$ 1,400								$ 1,400