Great Western Bancorp (GWB) 10-Q 12 May 16 2016 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Mar. 31, 2016	May. 04, 2016
Document Information [Abstract]
Entity Registrant Name	Great Western Bancorp, Inc.
Entity Central Index Key	1,613,665
Current Fiscal Year End Date	--09-30
Entity Filer Category	Non-accelerated Filer
Document Type	10-Q
Document Period End Date	Mar. 31, 2016
Document Fiscal Year Focus	2,016
Document Fiscal Period Focus	Q2
Amendment Flag	false
Entity Common Stock, Shares Outstanding		55,245,177

Consolidated Balance Sheets (Un

Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2016	Sep. 30, 2015
Assets
Cash and due from banks	$ 174,401	$ 237,770
Securities available for sale	1,328,685	1,327,327
Loans, net of unearned discounts and deferred fees, including $85,517 and $97,030 of loans covered by FDIC loss share agreements at March 31, 2016 and September 30, 2015, respectively, and $1,165,660 and $1,118,687 of loans and written loan commitments at fair value under the fair value option at March 31, 2016 and September 30, 2015, respectively, and $5,918 and $9,867 of loans held for sale at March 31, 2016 and September 30, 2015, respectively.	7,557,788	7,325,198
Allowance for loan losses	(61,917)	(57,200)
Net loans	7,495,871	7,267,998
Premises and equipment	99,018	97,550
Accrued interest receivable	39,487	44,077
Other repossessed property, including $0 and $61 of property covered by FDIC loss share arrangements at March 31, 2016 and September 30, 2015, respectively	12,204	15,892
FDIC indemnification asset	12,875	14,722
Goodwill	697,807	697,807
Core deposits and other intangibles	5,702	7,119
Net deferred tax assets	29,762	32,470
Other assets	46,483	55,922
Total assets	9,942,295	9,798,654
Deposits
Noninterest-bearing	1,503,981	1,368,453
Interest-bearing	6,208,748	6,018,612
Total deposits	7,712,729	7,387,065
Securities sold under agreements to repurchase	146,273	185,271
FHLB advances and other borrowings	370,000	581,000
Subordinated debentures and subordinated notes payable	90,764	90,727
Fair value of derivatives	74,197	53,613
Accrued interest payable	3,987	4,006
Accrued expenses and other liabilities	35,143	37,626
Total liabilities	8,433,093	8,339,308
Stockholders’ equity
Common stock, $0.01 par value, authorized 500,000,000 shares; 55,245,177 shares issued and outstanding at March 31, 2016 and 55,219,596 shares issued and outstanding at September 30, 2015	552	552
Additional paid-in capital	1,203,184	1,201,387
Retained earnings	300,757	255,089
Accumulated other comprehensive income	4,709	2,318
Total stockholders' equity	1,509,202	1,459,346
Total liabilities and stockholders' equity	$ 9,942,295	$ 9,798,654

Consolidated Balance Sheets (U3

Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2016	Sep. 30, 2015
Statement of Financial Position [Abstract]
Loans covered by FDIC loss share agreements	$ 85,517	$ 97,030
Loans and written loan commitments at fair value under the fair value option	1,165,660	1,118,687
Loans held for sale	5,918	9,867
Property covered under FDIC loss share agreements	$ 0	$ 61
Common stock, par value (in USD per share)	$ 0.01	$ 0.01
Common stock, shares authorized	500,000,000	500,000,000
Common stock, shares issued	55,245,177	55,219,596
Common stock, shares outstanding	55,245,177	55,219,596

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2016	Mar. 31, 2015
Interest and dividend income
Loans	$ 88,192	$ 82,394	$ 175,388	$ 166,738
Taxable securities	5,787	5,379	11,774	11,066
Nontaxable securities	12	13	24	26
Dividends on securities	222	258	436	508
Federal funds sold and other	94	160	169	444
Total interest and dividend income	94,307	88,204	187,791	178,782
Interest expense
Deposits	6,029	5,984	11,694	11,999
Securities sold under agreements to repurchase	132	150	271	296
FHLB advances and other borrowings	929	893	1,845	1,839
Related party notes payable	0	227	0	459
Subordinated debentures and subordinated notes payable	879	325	1,686	655
Total interest expense	7,969	7,579	15,496	15,248
Net interest income	86,338	80,625	172,295	163,534
Provision for loan losses	2,631	9,679	6,520	12,998
Net interest income after provision for loan losses	83,707	70,946	165,775	150,536
Noninterest income
Service charges and other fees	10,316	8,871	20,782	19,269
Wealth management fees	1,668	1,825	3,280	3,782
Net gain on sale of loans	1,204	1,580	2,474	3,124
Net gain (loss) on sale of securities	24	0		51
Reclassification adjustment for net gain (loss) realized in net income	24	0	(330)	(51)
Net increase in fair value of loans at fair value	35,955	15,208	21,054	32,308
Net realized and unrealized (loss) on derivatives	(40,893)	(21,698)	(31,454)	(46,303)
Other	725	1,150	1,836	2,605
Total noninterest income	8,999	6,936	17,642	14,836
Noninterest expense
Salaries and employee benefits	24,769	24,673	50,065	48,761
Data processing	5,008	4,708	10,254	9,536
Occupancy expenses	3,843	3,984	7,434	8,008
Professional fees	3,345	3,603	6,453	7,175
Communication expenses	928	1,225	1,862	2,398
Advertising	1,048	946	1,968	1,674
Equipment expense	931	925	1,835	1,881
Net loss recognized on repossessed property and other related expenses	210	2,634	100	4,480
Amortization of core deposits and other intangibles	708	2,313	1,417	4,626
Other	4,065	3,427	7,687	6,990
Total noninterest expense	44,855	48,438	89,075	95,529
Income before income taxes	47,851	29,444	94,342	69,843
Provision for income taxes	17,177	9,720	33,207	23,422
Net income	30,674	19,724	61,135	46,421
Other comprehensive income - change in net unrealized gain on securities available-for-sale (net of deferred income tax (expense) of $(6,128), and $(3,159) for the three months ended March 31, 2016 and 2015, respectively and $(1,466) and $(4,966) for the six months ended March 31, 2016 and 2015, respectively)	9,998	5,153	2,391	8,268
Comprehensive income	$ 40,672	$ 24,877	$ 63,526	$ 54,689
Basic earnings per common share
Weighted average shares outstanding	55,269,557	57,898,335	55,261,634	57,897,059
Earnings per share (in dollars per share)	$ 0.56	$ 0.34	$ 1.11	$ 0.80
Diluted earnings per common share
Weighted average shares outstanding	55,408,876	57,916,802	55,401,164	57,906,293
Diluted earnings per share (in dollars per share)	$ 0.55	$ 0.34	$ 1.10	$ 0.80
Dividends per share
Dividends paid	$ 7,734	$ 6,947	$ 15,467	$ 6,947
Dividends per share (in dollars per share)	$ 0.1399323682	$ 0.1199861792	$ 0.2798867656	$ 0.1199888236

Consolidated Statements of Com5

Consolidated Statements of Comprehensive Income (Unaudited) (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2016	Mar. 31, 2015
Income Statement [Abstract]
Income tax (expense) benefit	$ (6,128)	$ (3,159)	$ (1,466)	$ (4,966)

Consolidated Statement of Stock

Consolidated Statement of Stockholders' Equity (Unaudited) - USD ($) $ in Thousands	Total	Comprehensive Income	Common Stock Par Value	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)
Beginning balance at Sep. 30, 2014	$ 1,421,090		$ 579	$ 1,260,124	$ 166,544	$ (6,157)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	46,421	$ 46,421			46,421
Other comprehensive income, net of tax:
Net change in net unrealized gain (loss) on securities available for sale	8,268	8,268				8,268
Comprehensive income	54,689	54,689
Stock-based compensation	720			720
Common stock dividends, $0.14 and $0.12 in FY 2016 and FY 2015, respectively	(6,947)				(6,947)
Ending balance at Mar. 31, 2015	1,469,552		579	1,260,844	206,018	2,111
Beginning balance at Sep. 30, 2015	1,459,346		552	1,201,387	255,089	2,318
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	61,135	61,135			61,135
Other comprehensive income, net of tax:
Net change in net unrealized gain (loss) on securities available for sale	2,391	2,391				2,391
Comprehensive income	63,526	$ 63,526
Stock-based compensation	1,797			1,797
Common stock dividends, $0.14 and $0.12 in FY 2016 and FY 2015, respectively	(15,467)				(15,467)
Ending balance at Mar. 31, 2016	$ 1,509,202		$ 552	$ 1,203,184	$ 300,757	$ 4,709

Consolidated Statement of Stoc7

Consolidated Statement of Stockholders' Equity (Unaudited) (Parenthetical) - $ / shares	6 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Statement of Stockholders' Equity [Abstract]
Cash dividends paid on common stock (in USD per share)	$ 0.14	$ 0.12

Consolidated Statements of Cash

Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Operating activities
Net income	$ 61,135	$ 46,421
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	8,260	11,613
Amortization of FDIC indemnification asset	1,927	4,593
Net loss (gain) on sale of securities	330	(51)
Net gain on sale of loans	(2,474)	(3,124)
Net loss on FDIC indemnification asset	554	552
Net (gain) on sale of premises and equipment	(34)	(66)
Loss from sale/writedowns of repossessed property	100	4,480
Provision for loan losses	6,520	12,998
Stock-based compensation	1,797	720
Originations of residential real estate loans held for sale	(104,655)	(132,498)
Proceeds from sales of residential real estate loans held for sale	108,604	136,997
Deferred income taxes	1,242	(4,066)
Changes in:
Accrued interest receivable	4,590	4,676
Other assets	821	2,039
FDIC clawback liability	473	385
Accrued interest payable and other liabilities	17,609	24,272
Net cash provided by operating activities	106,799	109,941
Investing activities
Purchase of securities available for sale	(128,480)	(238,828)
Proceeds from sales of securities available for sale	24,996	55,149
Proceeds from maturities of securities available for sale	102,738	132,308
Net increase in loans	(236,955)	(300,513)
(Payment) reimbursement of covered losses from FDIC indemnification claims	(634)	1,637
Purchase of premises and equipment	(4,825)	(2,584)
Proceeds from sale of premises and equipment	641	1,438
Proceeds from sale of repossessed property	3,534	8,989
Purchase of FHLB stock	(11,815)	(3,037)
Proceeds from redemption of FHLB stock	20,433	7,149
Net cash used in investing activities	(230,367)	(338,292)
Financing activities
Net increase in deposits	325,664	435,518
Net (decrease) increase in securities sold under agreements to repurchase	(38,998)	1,656
Net (decrease) in FHLB advances and other borrowings	(211,000)	(100,075)
Dividends paid	(15,467)	(6,947)
Net cash provided by financing activities	60,199	330,152
Net (decrease) increase in cash and due from banks	(63,369)	101,801
Cash and due from banks, beginning of period	237,770	256,639
Cash and due from banks, end of period	174,401	358,440
Supplemental disclosure of cash flow information
Cash payments for interest	15,515	16,052
Cash payments for income taxes	33,777	33,980
Supplemental disclosure of noncash investing and financing activities
Loans transferred to repossessed properties	(786)	(6,914)
Repossessed property transferred to premises and equipment	$ (840)	$ 0

Nature of Operations and Summar

Nature of Operations and Summary of Significant Policies	6 Months Ended
	Mar. 31, 2016
Accounting Policies [Abstract]
Nature of Operations and Summary of Significant Policies	Nature of Operations and Summary of Significant Policies Nature of Operations Great Western Bancorp, Inc. (the “Company”) is a bank holding company organized under the laws of Delaware. The primary business of the Company is ownership of its wholly owned subsidiary, Great Western Bank (the “Bank”). The Bank is a full-service regional bank focused on relationship-based business and agribusiness banking in Arizona, Colorado, Iowa, Kansas, Missouri, Nebraska, and South Dakota. The Company and the Bank are subject to the regulation of certain federal and/or state agencies and undergo periodic examinations by those regulatory authorities. Substantially all of the Company’s income is generated from banking operations. Basis of Presentation The accompanying unaudited consolidated interim financial statements have been prepared in accordance with accounting principles generally accepted in the United States (“U.S. GAAP”) and reflect all adjustments that are, in the opinion of management, necessary for the fair presentation of the financial position and results of operations for the periods presented. All such adjustments are of a normal recurring nature. Certain previously reported amounts have been reclassified to conform to the current presentation. The unaudited interim consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements for the year ended September 30, 2015 , which includes a description of significant accounting policies. The results of operations for interim periods are not necessarily indicative of the results that may be expected for the year or any other period. The accompanying unaudited consolidated financial statements include the accounts and results of operations of the Company and its subsidiaries after elimination of all significant intercompany accounts and transactions. The preparation of unaudited consolidated financial statements in conformity with U.S. GAAP requires management to make certain estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. Actual results could differ from these estimates. Business Combinations The Company accounts for business combinations under the acquisition method of accounting in accordance with ASC 805, “Business Combinations” (“ASC 805”). The Company recognizes the fair value of the assets acquired and liabilities assumed, immediately expenses transaction costs and accounts for restructuring plans separately from the business combination. There is no separate recognition of the acquired allowance for loan losses on the acquirer’s balance sheet as credit related factors are incorporated directly into the fair value of the loans recorded at the acquisition date. The excess of the cost of the acquisition over the fair value of the net tangible and intangible assets acquired is recorded as goodwill. Alternatively, a bargain purchase gain is recorded equal to the amount by which the fair value of assets purchased exceeds the fair value of liabilities assumed and consideration paid. Results of operations of the acquired business are included in the consolidated statements of comprehensive income from the effective date of acquisition. Securities The Company classifies securities upon purchase in one of three categories: trading, held-to-maturity, or available-for-sale. Debt and equity securities held for resale are classified as trading. Debt securities for which the Company has the ability and positive intent to hold until maturity are classified as held-to-maturity. All other securities are classified as available-for-sale as they may be sold prior to maturity in response to changes in the Company’s interest rate risk profile, funding needs, demand for collateralized deposits by public entities or other reasons. Held-to-maturity securities are stated at amortized cost, which represents actual cost adjusted for premium amortization and discount accretion. Available-for-sale securities are stated at fair value, with unrealized gains and losses, net of related taxes, included in stockholders’ equity as a component of accumulated other comprehensive income (loss). Trading securities are stated at fair value. Realized and unrealized gains and losses from sales and fair value adjustments of trading securities are included in other noninterest income in the consolidated statements of comprehensive income. Purchases and sales of securities are recognized on a trade date basis. The cost of securities sold is based on the specific identification method. Declines in the fair value of investment securities available for sale (with certain exceptions for debt securities noted below) that are deemed to be other-than-temporary are recognized in earnings as a realized loss, and a new cost basis for the securities is established. In evaluating other-than-temporary impairment, management considers the length of time and extent to which the fair value has been less than amortized cost, the financial condition and near-term prospects of the issuer, and the intent and ability of the Company to retain its investment in the issuer for a period of time sufficient to allow for any anticipated recovery in fair value in the near term. Declines in the fair value of debt securities below amortized cost are deemed to be other-than-temporary in circumstances where: (1) the Company has the intent to sell a security; (2) it is more likely than not that the Company will be required to sell the security before recovery of its amortized cost basis; or (3) the Company does not expect to recover the entire amortized cost basis of the security. If the Company intends to sell a security or if it is more likely than not that the Company will be required to sell the security before recovery, an other-than-temporary impairment loss is recognized in earnings equal to the difference between the security’s amortized cost basis and its fair value. If the Company does not intend to sell the security or it is not more likely than not that it will be required to sell the security before recovery, the other-than-temporary impairment write-down is separated into an amount representing credit loss, which is recognized in earnings, and an amount related to all other factors, which is recognized in accumulated other comprehensive income (loss). Interest and dividends, including amortization of premiums and accretion of discounts, are recognized as interest or dividend income when earned. Realized gains and losses on sales (using the specific identification method) and declines in value judged to be other- than-temporary are included in noninterest income in the consolidated statements of comprehensive income. Loans The Company’s accounting method for loans differs depending on whether the loans were originated or purchased and, for purchased loans, whether the loans were acquired at a discount related to evidence of credit deterioration since date of origination. Originated Loans Loans that management has the intent and ability to hold for the foreseeable future, or until maturity or pay-off, generally are reported at their outstanding principal balance, adjusted for charge-offs, the allowance for loan losses, and any unamortized deferred fees or costs. Other fees, not associated with originating a loan are recognized as fee income when earned. Interest income on loans is accrued daily on the outstanding balances. Accrual of interest is discontinued when management believes, after considering collection efforts and other factors, the borrower’s financial condition is such that collection of interest is doubtful, which is generally at 90 days past due. Generally, when loans are placed on nonaccrual status, interest receivable is reversed against interest income in the current period. Interest payments received thereafter are applied as a reduction to the remaining principal balance as long as concern exists as to the ultimate collection of the principal. Loans are removed from nonaccrual status when they become current as to both principal and interest and concern no longer exists as to the collectability of principal and interest. The Company has elected to measure certain long-term loans and written loan commitments at fair value to assist in managing interest rate risk for longer-term loans. Fair value loans are fixed-rate loans having original maturities of 5 years or greater (typically between 5 and 15 years ) to our business and agribusiness banking customers to assist them in facilitating their risk management strategies. The fair value option was elected upon the origination or acquisition of these loans and written loan commitments. Interest income is recognized in the same manner on loans reported at fair value as on non-fair value loans, except in regard to origination fees and costs which are recognized immediately upon closing. The changes in fair value of long-term loans and written loan commitments at fair value are reported in noninterest income. For loans held for sale, loan fees charged or received on origination, net of certain direct loan origination costs, are recognized in income when the related loan is sold. For loans held for investment, loan fees, net of certain direct loan origination costs, are deferred, and the net amount is amortized as an adjustment of the related loan’s yield. The Company is generally amortizing these amounts over the contractual lives of the loans. Commitment fees are recognized as income when received. The Company grants commercial, agricultural, consumer, residential real estate, and other loans to customers primarily in Arizona, Colorado, Iowa, Kansas, Missouri, Nebraska, and South Dakota. The amount of collateral obtained, if deemed necessary, is based on management’s credit evaluation of the borrower. Collateral held varies but includes accounts receivable, inventory, property and equipment, residential real estate, and income-producing commercial and agricultural properties. Government guarantees are also obtained for some loans, which reduces the Company’s risk of loss. Loans originated and intended for sale in the secondary market are carried at the lower of cost or fair value. Loans held for sale include fixed rate single-family residential mortgage loans under contract to be sold in the secondary market. In most cases, loans are carried at cost and sold within 45 days . These loans are sold with the mortgage servicing rights released. Under limited circumstances, buyers may have recourse to return a purchased loan to the Company. Recourse conditions may include early payment default, breach of representation or warranties, or documentation deficiencies. Fair value of loans held for sale is determined based on prevailing market prices for loans with similar characteristics, sale contract prices, or, for certain portfolios, discounted cash flow analysis. Declines in fair value below cost (and subsequent recoveries) are recognized in net gain on sale of loans. Deferred fees and costs related to these loans are not amortized but are recognized as part of the cost basis of the loan at the time it is sold. Gains or losses on sales are recognized upon delivery and included in net gain on sale of loans. Purchased Loans Loans acquired (non-impaired and impaired) in a business acquisition are recorded at their fair value at the acquisition date. Credit discounts are included in the determination of fair value; therefore, an allowance for loan losses is not recorded at the acquisition date. In determining the acquisition date fair value of purchased loans with evidence of credit deterioration (“purchased impaired loans”), and in subsequent accounting, the Company generally aggregates impaired purchased consumer and certain smaller balance impaired commercial loans into pools of loans with common risk characteristics, while accounting for larger-balance impaired commercial loans individually. Expected cash flows at the acquisition date in excess of the fair value of loans are recorded as interest income over the life of the loans using a level-yield method. Management estimates the cash flows expected to be collected at acquisition and at subsequent measurement dates using internal risk models, which incorporate the estimate of key assumptions, such as default rates, loss severity, and prepayment speeds. Subsequent to the acquisition date, decreases in cash flows over those expected at the acquisition date are recognized by recording an allowance for loan losses. Subsequent increases in cash flow over those expected at the acquisition date are recognized as reductions to allowance for loan losses to the extent impairment was previously recognized and thereafter as interest income prospectively. For purchased loans not deemed impaired at the acquisition date, the difference between the fair value and the unpaid principal balance of the loan at acquisition date is amortized or accreted to interest income using the effective interest method over the remaining period to contractual maturity. Credit Risk Management The Company’s strategy for credit risk management includes well-defined, centralized credit policies, uniform underwriting criteria and ongoing risk monitoring and review processes for all credit exposures. The strategy also emphasizes diversification on a geographic, industry, and customer level; regular credit examinations; and management reviews of loans exhibiting deterioration of credit quality. The credit risk management strategy also includes a credit risk assessment process that performs assessments of compliance with commercial and consumer credit policies, risk ratings, and other critical credit information. Loan decisions are documented with respect to the borrower’s business, purpose of the loan, evaluation of the repayment sources, and the associated risks, evaluation of collateral, covenants and monitoring requirements, and risk rating rationale. The Company categorizes its loan portfolio into six classes, which is the level at which it develops and documents a systematic methodology to determine the allowance for loan losses. The Company’s six loan portfolio classes are residential real estate, commercial real estate, commercial non real estate, agriculture, consumer and other lending. The residential real estate lending class includes loans made to consumer customers including residential mortgages, residential construction loans and home equity loans and lines. These loans are typically fixed rate loans secured by residential real estate. Home equity lines are revolving accounts giving the borrower the ability to draw and repay balances repeatedly, up to a maximum commitment, and are secured by residential real estate. Home equity lines typically have variable rate terms which are benchmarked to a prime rate. Historical loss history is the primary factor in determining the allowance for loan losses for the residential real estate lending class. Key risk characteristics relevant to residential real estate lending class loans primarily relate to the borrower’s capacity and willingness to repay and include unemployment rates and other economic factors, and customer payment history. These risk characteristics, among others, are reflected in the environmental factors considered in determining the allowance for loan losses. The commercial real estate lending class includes loans made to small and middle market businesses, including multifamily properties. Loans in this class are secured by commercial real estate. Historical loss history and updated loan-to-value information on collateral-dependent loans are the primary factors in determining the allowance for loan losses for the commercial real estate lending class. Key risk characteristics relevant to the commercial real estate lending class include the industry and geography of the borrower’s business, purpose of the loan, repayment sources, borrower’s debt capacity and financial performance, loan covenants, and nature of pledged collateral. We consider these risk characteristics in assigning risk ratings and estimating environmental factors considered in determining the allowance for loan losses. The commercial non real estate lending class includes loans made to small and middle market businesses, and loans made to public sector customers. Loans in this class are generally secured by business assets and guaranteed by owners; cashflows are most often our primary source of repayment. Historical loss history and updated loan-to-value information on collateral-dependent loans are the primary factors in determining the allowance for loan losses for the commercial non real estate lending class. Key risk characteristics relevant to the commercial non real estate lending class include the industry and geography of the borrower’s business, purpose of the loan, repayment sources, borrower’s debt capacity and financial performance, loan covenants, and nature of pledged collateral. We consider these risk characteristics in assigning risk ratings and estimating environmental factors considered in determining the allowance for loan losses. The agriculture lending class includes loans made to small and mid-size agricultural businesses and individuals. Loans in this class are generally secured by operating assets and guaranteed by owners; cashflows are most often our primary source of repayment. Historical loss history and updated loan-to-value information on collateral-dependent loans are the primary factors in determining the allowance for loan losses for the agriculture lending class. Key risk characteristics relevant to the agriculture lending class include the geography of the borrower’s operations, commodity prices and weather patterns, purpose of the loan, repayment sources, borrower’s debt capacity and financial performance, loan covenants, and nature of pledged collateral. We consider these risk characteristics in assigning risk ratings and estimating environmental factors considered in determining the allowance for loan losses. The consumer lending class includes loans made to consumer customers including loans secured by automobiles and other installment loans, and the other lending class includes credit card loans and unsecured revolving credit lines. Historical loss history is the primary factor in determining the allowance for loan losses for the consumer and other lending classes. Key risk characteristics relevant to loans in the consumer and other lending classes primarily relate to the borrower’s capacity and willingness to repay and include unemployment rates and other economic factors, and customer payment and overall credit history. These risk characteristics, among others, are reflected in the environmental factors considered in determining the allowance for loan losses. The Company assigns all non-consumer loans a credit quality risk rating. These ratings are Pass, Watch, Substandard, Doubtful, and Loss. Loans with a Pass and Watch rating represent those loans not classified on the Company’s rating scale for problem credits, with loans with a Watch rating being monitored and updated at least quarterly by management. Substandard loans are those where a well-defined weakness has been identified that may put full collection of contractual debt at risk. Doubtful loans are those where a well-defined weakness has been identified and a loss of contractual debt is probable. Substandard and doubtful loans are monitored and updated monthly. All loan risk ratings are updated and monitored on a continuous basis. The Company generally does not risk rate consumer loans unless a default event such as bankruptcy or extended nonperformance takes place. Alternatively, standard credit scoring systems are used to assess credit risks of consumer loans. Troubled Debt Restructurings (“TDRs”) Loans modified under troubled debt restructurings involve granting a concession to a borrower who is experiencing financial difficulty. These concessions could include a reduction in the interest rate on the loan, payment extensions, forgiveness of principal, forbearance, or other actions intended to maximize collection, which generally would not otherwise be considered. Our TDRs include performing and nonperforming TDRs, which consist of loans that continue to accrue interest at the loan's original interest rate as we expect to collect the remaining principal and interest on the loan, and nonaccrual TDRs, which include loans that are in a nonaccrual status and are no longer accruing interest, as we do not expect to collect the full amount of principal and interest owned from the borrower on these loans. At the time of modification (except for loans on nonaccrual status), a TDR is classified as nonperforming TDR until a six -month payment history of principal and interest payments, in accordance with the terms of the loan modification, is sustained, at which time we move the loan to a performing status (performing TDR). If we do not expect to collect all principal and interest on the loan, the modified loan is classified as a nonaccrual TDR. All TDRs are accounted for as impaired loans and are included in our analysis of the allowance for loan losses. A TDR that has been renewed for a borrower who is no longer experiencing financial difficulty and which yields a market rate of interest at the time of a renewal is no longer considered a TDR. Allowance for Loan Losses (“ALL”) and Unfunded Commitments The Company maintains an allowance for loan losses at a level management believes is appropriate to reserve for credit losses inherent in our loan portfolio. The allowance for loan losses is determined based on an ongoing evaluation, driven primarily by monitoring changes in loan risk grades, delinquencies, and other credit risk indicators, which is inherently subjective. The Company considers the uncertainty related to certain industry sectors and the extent of credit exposure to specific borrowers within the portfolio. In addition, consideration is given to concentration risks associated with the various loan portfolios and current economic conditions that might impact the portfolio. The Company also considers changes, if any, in underwriting activities, the loan portfolio composition (including product mix and geographic, industry, or customer-specific concentrations), trends in loan performance, the level of allowance coverage relative to similar banking institutions and macroeconomic factors, such as changes in unemployment rates, gross domestic product, and consumer bankruptcy filings. All of these estimates are susceptible to significant change. Changes to the allowance for loan losses are made by charges to the provision for loan losses, which is reflected in the consolidated statements of comprehensive income. Past due status is monitored as an indicator of credit deterioration. Loans that are 90 days or more past due are put on nonaccrual status unless the loan is well secured and in the process of collection. Loans deemed to be uncollectible are charged off against the allowance for loan losses. Recoveries of amounts previously charged-off are credited to the allowance for loan losses. The allowance for loan losses consist of reserves for probable losses that have been identified related to specific borrowing relationships that are individually evaluated for impairment (“specific reserve”), as well as probable losses inherent in our loan portfolio that are not specifically identified (“collective reserve”). The specific reserve relates to impaired loans. A loan is impaired when, based on current information and events, it is probable the Company will be unable to collect all amounts due (interest as well as principal) according to the contractual terms of the loan agreement. Specific reserves are determined on a loan-by-loan basis based on management’s best estimate of the Company’s exposure, given the current payment status of the loan, the present value of expected payments, and the value of any underlying collateral. Impaired loans also include loans modified in troubled debt restructurings. Generally, the impairment related to troubled debt restructurings is measured based on the fair value of the collateral, less cost to sell, or the present value of expected payments relative to the unpaid principal balance. If the impaired loan is identified as collateral dependent, then the fair value of the collateral method of measuring the amount of the impairment is utilized. This method requires obtaining an independent appraisal of the collateral and applying a discount factor to the appraised value, if necessary, and including costs to sell. Management’s estimate for collective reserves reflects losses incurred in the loan portfolio as of the consolidated balance sheet reporting date. Incurred loss estimates primarily are based on historical loss experience and portfolio mix. Incurred loss estimates may be adjusted for qualitative factors such as current economic conditions and current portfolio trends including credit quality, concentrations, aging of the portfolio, and/or significant policy and underwriting changes. The Company maintains an ALL for acquired impaired loans accounted for under ASC 310-30, resulting from decreases in expected cash flows arising from the periodic revaluation of these loans Any decrease in expected cash flows in the individual loan pool is generally recognized in the current provision for loan losses. Any increase in expected cash flows is generally not recognized immediately but is instead reflected as an adjustment to the related loan or pool's yield on a prospective basis once any previously recorded provision for loan loss has been recognized. For acquired nonimpaired loans accounted for under ASC 310-20, the Company utilizes methods to estimate the required allowance for loan losses similar to originated loans; the required reserve is compared to the net carrying value of each acquired nonimpaired loan (by segment) to determine if a provision is required. While management uses the best information available to establish the allowance for loan losses, future adjustments may be necessary if economic conditions differ substantially from the assumptions used in performing the estimates. Unfunded residential mortgage loan commitments entered into in connection with mortgage loans to be held for sale are considered derivatives and are recorded at fair value and included in other liabilities on the consolidated balance sheets with changes in fair value recorded in other interest income. All other unfunded loan commitments are generally related to providing credit facilities to customers and are not considered derivatives. For purchased loans, the fair value of the unfunded credit commitments is considered in determination of the fair value of the loans recorded at the date of acquisition. Reserves for credit exposure on all other unfunded credit commitments are recorded in other liabilities on the consolidated balance sheets. FDIC Indemnification Asset and Clawback Liability In conjunction with a Federal Deposit Insurance Corporation (“FDIC”)-assisted transaction of TierOne Bank in 2010, the Company entered into two loss share agreements with the FDIC, one covering certain single family residential mortgage loans with the claim period ending June 2020 and one covering commercial loans and other assets, in which the claim period ended in June 2015. The agreements cover a portion of realized losses on loans, foreclosed real estate and certain other assets. The Company has recorded assets on the consolidated balance sheets (i.e. indemnification assets) representing estimated future amounts recoverable from the FDIC. Fair values of loans covered by the loss sharing agreements at the acquisition date were estimated based on projected cash flows available based on the expected probability of default, default timing and loss given default, the expected reimbursement rates (generally 80% ) from the FDIC and other relevant terms of the loss sharing agreements. The initial fair value was established by discounting these expected cash flows with a market discount rate for instruments with like maturity and risk characteristics. The loss share assets are measured separately from the related loans and foreclosed real estate and recorded as an FDIC indemnification asset on the consolidated balance sheets because they are not contractually embedded in the loans and are not transferable with the loans should the Company choose to dispose of them. Subsequent to the acquisition date, reimbursements received from the FDIC for actual incurred losses reduce the carrying amount of the loss share assets. Reductions to expected losses on covered assets, to the extent such reductions to expected losses are the result of an improvement to the actual or expected cash flows from the covered assets, also reduce the carrying amount of the loss share assets. The rate of accretion of the indemnification asset discount included in interest income slows to mirror the accelerated accretion of the loan discount. Additional expected losses on covered assets, to the extent such expected losses result in the recognition of an allowance for loan losses, increase the carrying amount of the loss share assets. A related increase in the value of the indemnification asset up to the amount covered by the FDIC is calculated based on the reimbursement rates from the FDIC and is included in other noninterest income. The corresponding loan accretion or amortization is recorded as a component of interest income on the consolidated statements of comprehensive income. Although these assets are contractual receivables from the FDIC, there are no contractual interest rates. As part of the loss sharing agreements, the Company also assumed a liability (“FDIC Clawback Liability”) to be paid within 45 days subsequent to the maturity or termination of the loss sharing agreements that is contingent upon actual losses incurred over the life of the agreements relative to expected losses considered in the consideration paid at acquisition date and the amount of losses reimbursed to the Company under the loss sharing agreements. The liability was recorded at fair value as of the acquisition date. The fair value was based on a discounted cash flow calculation that considered the formula defined in the loss sharing agreements and projected losses. The difference between the fair value at acquisition date and the projected losses is amortized through other noninterest expense. As projected losses and reimbursements are updated, as described above, the FDIC Clawback Liability is adjusted and a gain or loss is recorded in other noninterest expense. Core Deposits and Other Intangibles Intangible assets consist of core deposits, brand intangible, customer relationships, and other intangibles. Core deposits represent the identifiable intangible value assigned to core deposit bases arising from purchase acquisitions. Brand intangible represents the value associated with the Bank charter. Customer relationships intangible represents the identifiable intangible value assigned to customer relationships arising from a purchase acquisition. Other intangibles represent contractual franchise arrangements under which the franchiser grants the franchisee the right to perform certain functions within a designated geographical area. The methods and lives used to amortize intangible assets are as follows: Intangible Method Years Core deposit Straight-line or effective yield 5 Brand intangible Straight-line 15 Customer relationships Straight-line 8.5 Other intangibles Straight-line 5 Intangible assets are evaluated for impairment whenever events or changes in circumstances indicate that the carrying value may not be recoverable. No intangible asset impairments were recognized during the periods ended March 31, 2016 and 2015 . Derivatives The Company maintains an overall interest rate risk management strategy that permits the use of derivative instruments to modify exposure to interest rate risk. The Company enters into interest rate swap contracts to offset the interest rate risk associated with borrowers who lock in long-term fixed rates (greater than or equal to 5 years to maturity) through a fixed rate loan. These contracts do not qualify for hedge accounting. Generally, under these swaps, the Company agrees with various swap counterparties to exchange the difference between fixed-rate and floating-rate interest amounts based upon notional principal amounts. These interest rate derivative instruments are recognized as assets and liabilities on the consolidated balance

New Accounting Pronouncements

New Accounting Pronouncements	6 Months Ended
	Mar. 31, 2016
Accounting Changes and Error Corrections [Abstract]
New Accounting Pronouncements	New Accounting Pronouncements In March 2016, the FASB issued ASU No. 2016-09, Compensation - Stock Based Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting , which addresses several aspects of the accounting for share-based payment transactions, including the income tax consequences, classification of awards as either equity or liabilities, and classification on the statement of cash flows. ASU 2016-09 is effective for all entities for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2016. Earlier application is permitted. If an entity early adopts the amendments in an interim period, any adjustments should be reflected as of the beginning of the fiscal year that includes that interim period. An entity that elects early adoption must adopt all of the amendments in the same period. The Company is currently evaluating the potential impact of ASU 2016-09 on our financial statements. In February 2016, the FASB issued ASU No. 2016-02 , Leases (Topic 842) , which requires that lessees recognize the assets and liabilities arising from leases on the balance sheet. ASU 2015-16 will be effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2018. The Company is currently evaluating the potential impact of ASU 2016-02 on our financial statements. In January 2016, the FASB issued ASU No. 2016-01, Financial Instruments - Overall (Subtopic 825-10) - Recognition and Measurement of Financial Assets and Financial Liabilities, which addresses certain aspects of recognition, measurement, presentation and disclosure of financial instruments. ASU 2016-01 will be effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2017, with early adoption permitted. The Company is currently evaluating the potential impact of ASU 2016-01 on our financial statements. In September 2015, the FASB issued ASU No. 2015-16, Business Combinations (Topic 805) - Simplifying the Accounting for Measurement-Period Adjustments, which requires that adjustments to provisional amounts that are identified during the measurement period of a business combination be recognized in the reporting period in which the adjustment amounts are determined. Furthermore, the income statement effects of such adjustments, if any, must be calculated as if the accounting had been completed at the acquisition date. The portion of the amount recorded in current-period earnings that would have been recorded in previous reporting periods if the adjustment to the provisional amounts had been recognized as of the acquisition date. Under previous guidance, adjustments to provisional amounts identified during the measurement period are to be recognized retrospectively. ASU 2015-16 will be effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2015. Earlier application is permitted for financial statements that have not been issued, therefore the Company has elected to early adopt this ASU for fiscal year 2016 . There is no impact to our financial statements in the current quarter. In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606) , which does not apply to financial instruments. The core principle of the guidance is that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods and services. ASU 2014-09 is effective for annual reporting periods beginning after December 15, 2016, including interim periods within that reporting period. The amendments can be applied retrospectively to each prior reporting period or retrospectively with the cumulative effect of initially applying this ASU recognized at the date of initial application. Early application is not permitted. The Company is assessing the impact of ASU 2014-09 on its accounting and disclosures. In August 2015, the FASB issued ASU No. 2015-14 which deferred the effective date of ASU No. 2014-09 until annual reporting periods beginning after December 15, 2017. No other revisions were made to ASU 2014-09. The Company is currently evaluating the potential impact of ASU 2014-09 on our financial statements.

Securities Available for Sale

Securities Available for Sale	6 Months Ended
	Mar. 31, 2016
Investments, Debt and Equity Securities [Abstract]
Securities Available for Sale	Securities Available for Sale The amortized cost and approximate fair value of investments in securities, all of which are classified as available for sale according to management’s intent, are summarized as follows (in thousands): Amortized Cost Gross Gross Estimated Fair Value As of March 31, 2016 U.S. Treasury securities $ 226,497 $ 4,340 $ — $ 230,837 U.S. Agency securities 74,480 516 — 74,996 Mortgage-backed securities: Government National Mortgage Association 743,435 4,008 (3,033 ) 744,410 Federal National Mortgage Association 135,323 616 — 135,939 Small Business Assistance Program 133,878 1,123 — 135,001 States and political subdivision securities 1,458 — — 1,458 Corporate debt securities 4,997 — (6 ) 4,991 Other 1,006 47 — 1,053 Total $ 1,321,074 $ 10,650 $ (3,039 ) $ 1,328,685 Amortized Cost Gross Gross Estimated Fair Value As of September 30, 2015 U.S. Treasury securities $ 250,986 $ 3,811 $ — $ 254,797 U.S. Agency securities 74,412 643 — 75,055 Mortgage-backed securities: Government National Mortgage Association 842,460 3,663 (4,503 ) 841,620 Federal National Mortgage Association 46,449 96 — 46,545 Small Business Assistance Program 101,415 233 (213 ) 101,435 States and political subdivision securities 1,849 1 — 1,850 Corporate debt securities 4,996 — (13 ) 4,983 Other 1,006 36 — 1,042 Total $ 1,323,573 $ 8,483 $ (4,729 ) $ 1,327,327 The amortized cost and approximate fair value of debt securities available for sale as of March 31, 2016 and September 30, 2015 , by contractual maturity, are shown below. Maturities of mortgage-backed securities may differ from contractual maturities because the mortgages underlying the securities may be called or repaid without any penalties. March 31, 2016 September 30, 2015 (In Thousands) Amortized Cost Estimated Fair Value Amortized Cost Estimated Fair Value Due in one year or less $ 74,825 $ 75,341 $ 76,261 $ 76,905 Due after one year through five years 231,645 235,979 255,982 259,780 Due after five years through ten years 962 962 — — 307,432 312,282 332,243 336,685 Mortgage-backed securities 1,012,636 1,015,350 990,324 989,600 Securities without contractual maturities 1,006 1,053 1,006 1,042 Total $ 1,321,074 $ 1,328,685 $ 1,323,573 $ 1,327,327 Proceeds from sales of securities available for sale were $25.0 million and $0 million for the three months ended March 31, 2016 and 2015 , respectively, and $25.0 million and $55.1 million for the six months ended March 31, 2016 and 2015 , respectively. Gross gains (pre-tax) of $0 million and $0 million and gross losses (pre-tax) of $0 million and $0 million were realized on the sales for the three months ended March 31, 2016 and 2015 , respectively. Gross gains (pre-tax) of $0 million and $0.6 million and gross losses (pre-tax) of $0 million and $0.5 million were realized on the sales for the six months ended March 31, 2016 and 2015 , respectively, using the specific identification method. The Company recognized an other than temporary impairment in net loss on sale of securities in the consolidated statements of comprehensive income of $0 million and $0.4 million on two security holdings attributable to credit for the three and six months ended March 31, 2016 . There was no other than temporary impairment recognized for the three and six months ended March 31, 2015 . Securities with an estimated fair value of approximately $888.9 million and $894.3 million at March 31, 2016 and September 30, 2015 , respectively, were pledged as collateral on public deposits, securities sold under agreements to repurchase, and for other purposes as required or permitted by law. The counterparties do not have the right to sell or pledge the securities the Company has pledged as collateral. As detailed in the following tables, certain investments in debt securities, which are approximately 25% and 36% of the Company’s investment portfolio at March 31, 2016 and September 30, 2015 , respectively, are reported in the consolidated financial statements at an amount less than their amortized cost. Based on evaluation of available evidence, including recent changes in market interest rates, credit rating information, implicit or explicit government guarantees, and information obtained from regulatory filings, management believes the declines in fair value of these securities are temporary. As the Company does not intend to sell the securities and it is not more likely than not that the Company will be required to sell the securities before the recovery of their amortized cost basis, which may be maturity, the Company does not consider the securities to be other than temporarily impaired at March 31, 2016 or September 30, 2015 . The following table presents the Company’s gross unrealized losses and approximate fair value in investments, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position (in thousands): March 31, 2016 Less than 12 months 12 months or more Total Estimated Fair Value Unrealized Losses Estimated Fair Value Unrealized Losses Estimated Fair Value Unrealized Losses U.S. Treasury securities $ — $ — $ — $ — $ — $ — U.S. Agency securities — — — — — — Mortgage-backed securities 24,380 (43 ) 305,508 (2,990 ) 329,888 (3,033 ) Corporate debt securities 4,992 (6 ) — — 4,992 (6 ) Total $ 29,372 $ (49 ) $ 305,508 $ (2,990 ) $ 334,880 $ (3,039 ) September 30, 2015 Less than 12 months 12 months or more Total Estimated Fair Value Unrealized Losses Estimated Fair Value Unrealized Losses Estimated Fair Value Unrealized Losses U.S. Treasury securities $ — $ — $ — $ — $ — $ — U.S. Agency securities — — — — — — Mortgage-backed securities 58,604 (236 ) 412,058 (4,480 ) 470,662 (4,716 ) Corporate debt securities 4,984 (13 ) — — 4,984 (13 ) Total $ 63,588 $ (249 ) $ 412,058 $ (4,480 ) $ 475,646 $ (4,729 ) As of March 31, 2016 and September 30, 2015 , the Company had 25 and 31 securities, respectively, in an unrealized loss position. The majority of the Company’s investments in nonmarketable equity securities are stock of the Federal Home Loan Bank ("FHLB"). The carrying value of Federal Home Loan Bank stock was $27.1 million and $35.7 million as of March 31, 2016 and September 30, 2015 , respectively, and is reported in other assets on the consolidated balance sheets. No indicators of impairment related to FHLB stock were identified during the three and six months ended March 31, 2016 and 2015 , respectively. The components of accumulated other comprehensive income (loss) from net unrealized gains (losses) on securities available for sale for the three and six months ended March 31, 2016 and 2015 , respectively are as follows (in thousands): Three Months Ended Six Months Ended 2016 2015 2016 2015 Beginning balance accumulated other comprehensive income (loss) $ (5,289 ) $ (3,042 ) $ 2,318 $ (6,157 ) Net unrealized holding gain arising during the period 16,102 8,312 4,187 13,285 Reclassification adjustment for net gain (loss) realized in net income 24 — (330 ) (51 ) Net change in unrealized gain before income taxes 16,126 8,312 3,857 13,234 Income tax (expense) (6,128 ) (3,159 ) (1,466 ) (4,966 ) Net change in unrealized gain on securities after taxes 9,998 5,153 2,391 8,268 Ending balance accumulated other comprehensive income $ 4,709 $ 2,111 $ 4,709 $ 2,111

Loans

Loans	6 Months Ended
	Mar. 31, 2016
Receivables [Abstract]
Loans	Loans The composition of loans as of March 31, 2016 and September 30, 2015 , is as follows (in thousands): March 31, 2016 September 30, 2015 Residential real estate $ 909,590 $ 921,827 Commercial real estate 3,078,028 2,845,748 Commercial non real estate 1,588,356 1,610,828 Agriculture 1,900,013 1,861,465 Consumer 64,465 73,049 Other 39,510 38,371 Ending balance 7,579,962 7,351,288 Less: Unamortized discount on acquired loans (16,829 ) (19,264 ) Unearned net deferred fees and costs and loans in process (5,345 ) (6,826 ) Total $ 7,557,788 $ 7,325,198 The loan breakouts above include loans covered by FDIC loss sharing agreements totaling $85.5 million and $97.0 million as of March 31, 2016 and September 30, 2015 , respectively, residential real estate loans held for sale totaling $5.9 million and $9.9 million at March 31, 2016 and September 30, 2015 , respectively, and $1.17 billion and $1.12 billion of loans and written loan commitments accounted for at fair value at March 31, 2016 and September 30, 2015 , respectively. Unamortized net deferred fees and costs totaled $7.2 million and $7.5 million as of March 31, 2016 and September 30, 2015 , respectively. Loans in process represent loans that have been funded as of the balance sheet dates but not classified into a loan category and loan payments received as of the balance sheet dates that have not been applied to individual loan accounts. Loans in process totaled $(1.9) million and $(0.7) million at March 31, 2016 and September 30, 2015 , respectively. Loans guaranteed by agencies of the U.S. government totaled $129.8 million and $105.0 million at March 31, 2016 and September 30, 2015 , respectively. Principal balances of residential real estate loans sold totaled $50.4 million and $69.6 million for the three months ended March 31, 2016 and 2015 , respectively, and $108.6 million and $133.9 million for the six months ended March 31, 2016 and 2015 , respectively. Nonaccrual The following table presents the Company’s nonaccrual loans at March 31, 2016 and September 30, 2015 (in thousands), excluding loans acquired with deteriorated credit quality. Loans greater than 90 days past due and still accruing interest as of March 31, 2016 and September 30, 2015 , were not significant. Nonaccrual loans March 31, 2016 September 30, 2015 Residential real estate $ 6,853 $ 7,642 Commercial real estate 9,932 9,556 Commercial non real estate 9,944 14,281 Agriculture 17,377 24,569 Consumer 60 107 Total $ 44,166 $ 56,155 Credit Quality Information The composition of the loan portfolio by internally assigned grade is as follows as of March 31, 2016 and September 30, 2015 . This table (in thousands) is presented net of unamortized discount on acquired loans and excludes loans measured at fair value with changes in fair value reported in earnings of $1.17 billion at March 31, 2016 and $1.12 billion at September 30, 2015 : As of March 31, 2016 Residential Commercial Commercial Agriculture Consumer Other Total Credit Risk Profile by Internally Assigned Grade Grade: Pass $ 797,470 $ 2,589,340 $ 1,007,498 $ 1,257,519 $ 63,918 $ 39,510 $ 5,755,255 Watchlist 4,454 98,291 53,285 177,317 250 — 333,597 Substandard 11,731 59,036 32,728 118,390 279 — 222,164 Doubtful 107 186 652 — — — 945 Loss — — — — — — — Ending balance 813,762 2,746,853 1,094,163 1,553,226 64,447 39,510 6,311,961 Loans covered by FDIC loss sharing agreements 85,517 — — — — — 85,517 Total $ 899,279 $ 2,746,853 $ 1,094,163 $ 1,553,226 $ 64,447 $ 39,510 $ 6,397,478 As of September 30, 2015 Residential Commercial Commercial Agriculture Consumer Other Total Credit Risk Profile by Internally Assigned Grade Grade: Pass $ 799,359 $ 2,384,980 $ 1,053,091 $ 1,272,312 $ 72,705 $ 38,371 $ 5,620,818 Watchlist 4,890 66,024 50,242 189,144 78 — 310,378 Substandard 11,877 56,905 60,801 53,837 223 — 183,643 Doubtful 323 200 682 256 7 — 1,468 Loss — — — — — — — Ending balance 816,449 2,508,109 1,164,816 1,515,549 73,013 38,371 6,116,307 Loans covered by FDIC loss sharing agreements 97,030 — — — — — 97,030 Total $ 913,479 $ 2,508,109 $ 1,164,816 $ 1,515,549 $ 73,013 $ 38,371 $ 6,213,337 Past Due Loans The following table (in thousands) presents the Company’s past due loans at March 31, 2016 and September 30, 2015 . This table is presented net of unamortized discount on acquired loans and excludes loans measured at fair value with changes in fair value reported in earnings of $1.17 billion at March 31, 2016 and $1.12 billion at September 30, 2015 . As of March 31, 2016 30-59 Days 60-89 Days 90 Days or Greater Past Due Total Current Total Residential real estate $ 1,669 $ 31 $ 2,084 $ 3,784 $ 809,978 $ 813,762 Commercial real estate 1,281 165 6,020 7,466 2,739,387 2,746,853 Commercial non real estate 4,484 266 6,145 10,895 1,083,268 1,094,163 Agriculture 1,292 662 7,276 9,230 1,543,996 1,553,226 Consumer 100 18 8 126 64,321 64,447 Other — — — — 39,510 39,510 Ending balance 8,826 1,142 21,533 31,501 6,280,460 6,311,961 Loans covered by FDIC loss sharing agreements 2,392 295 192 2,879 82,638 85,517 Total $ 11,218 $ 1,437 $ 21,725 $ 34,380 $ 6,363,098 $ 6,397,478 As of September 30, 2015 30-59 Days 60-89 Days 90 Days or Greater Past Due Total Current Total Residential real estate $ 486 $ 858 $ 2,776 $ 4,120 $ 812,329 $ 816,449 Commercial real estate 1,708 1,204 4,247 7,159 2,500,950 2,508,109 Commercial non real estate 697 7,944 4,072 12,713 1,152,103 1,164,816 Agriculture 2,161 175 6,264 8,600 1,506,949 1,515,549 Consumer 232 8 37 277 72,736 73,013 Other — — — — 38,371 38,371 Ending balance 5,284 10,189 17,396 32,869 6,083,438 6,116,307 Loans covered by FDIC loss sharing agreements 2,455 594 873 3,922 93,108 97,030 Total $ 7,739 $ 10,783 $ 18,269 $ 36,791 $ 6,176,546 $ 6,213,337 Impaired Loans The following table presents the Company’s impaired loans (in thousands). This table excludes loans covered by FDIC loss sharing agreements: March 31, 2016 September 30, 2015 Recorded Unpaid Related Recorded Unpaid Related Impaired loans: With an allowance recorded: Residential real estate $ 11,942 $ 12,644 $ 3,731 $ 12,364 $ 12,602 $ 2,784 Commercial real estate 86,212 86,984 7,421 67,751 69,722 4,644 Commercial non real estate 34,053 34,311 5,936 65,495 76,647 5,657 Agriculture 118,390 119,514 6,963 54,093 54,699 3,950 Consumer 293 439 56 230 359 50 Total $ 250,890 $ 253,892 $ 24,107 $ 199,933 $ 214,029 $ 17,085 There are no impaired loans without a valuation allowance, other than those loans for which the Company has claim to collateral with value(s) in excess of the outstanding loan amount, after allowing for the cost of liquidating the collateral as of March 31, 2016 and September 30, 2015 . The average recorded investment on impaired loans and interest income recognized on impaired loans for the three and six months ended March 31, 2016 and 2015 , respectively, are as follows: Three Months Ended March 31, 2016 Three Months Ended March 31, 2015 Six Months Ended Six Months Ended Average Interest Income Recognized while on Impaired Status Average Interest Income Recognized while on Impaired Status Average Interest Income Recognized while on Impaired Status Average Interest Income Recognized while on Impaired Status Residential real estate $ 12,124 $ 290 $ 12,379 $ 783 $ 12,204 $ 439 $ 12,288 $ 945 Commercial real estate 83,642 2,004 74,990 4,622 78,345 3,473 70,711 6,392 Commercial non real estate 40,450 766 40,210 2,644 48,798 1,122 37,647 3,445 Agriculture 109,473 3,256 40,056 1,440 91,013 5,695 38,546 1,787 Consumer 308 25 246 42 282 42 257 51 Total $ 245,997 $ 6,341 $ 167,881 $ 9,531 $ 230,642 $ 10,771 $ 159,449 $ 12,620 Valuation adjustments made to repossessed properties for the three months ended March 31, 2016 and 2015 , totaled $0.5 million and $2.2 million , respectively and $0.5 million and $4.3 million for the six months ended March 31, 2016 and 2015 , respectively. The adjustments are included in noninterest expense. Troubled Debt Restructurings Included in certain loan categories in the impaired loans are troubled debt restructurings (“TDRs”) that were classified as impaired. These TDRs do not include purchased credit impaired loans. When the Company grants concessions to borrowers such as reduced interest rates or extensions of loan periods that would not be considered other than because of borrowers’ financial difficulties, the modification is considered a TDR. Specific reserves included in the allowance for loan losses for TDRs were $7.9 million and $3.6 million at March 31, 2016 and September 30, 2015 , respectively. Commitments to lend additional funds to borrowers whose loans were modified in a TDR were $1.7 million and $2.3 million as of March 31, 2016 and September 30, 2015 , respectively. The following table presents the recorded value of the Company’s TDR balances as of March 31, 2016 and September 30, 2015 (in thousands): March 31, 2016 September 30, 2015 Accruing Nonaccrual Accruing Nonaccrual Residential real estate $ 377 $ 1,142 $ 452 $ 1,547 Commercial real estate 39,391 2,441 30,917 4,725 Commercial non real estate 7,641 1,686 8,928 833 Agriculture 46,527 6,205 20,041 6,857 Consumer 19 18 33 4 Total $ 93,955 $ 11,492 $ 60,371 $ 13,966 The following table presents a summary of all accruing loans restructured in TDRs during the three months ended March 31, 2016 and 2015 , respectively: Three Months Ended March 31, 2016 2015 Recorded Investment Recorded Investment ($ in thousands) Number Pre- Post- Number Pre- Post- Residential real estate Rate modification — $ — $ — 1 $ 15 $ 15 Term extension — — — — — — Payment modification — — — — — — Bankruptcy — — — — — — Other — — — 1 21 21 Total residential real estate — — — 2 36 36 Commercial real estate Rate modification — — — — — — Term extension — — — 1 90 — Payment modification — — — 4 3,660 3,660 Bankruptcy — — — 1 498 498 Other 3 6,714 6,714 — — — Total commercial real estate 3 6,714 6,714 6 4,248 4,158 Commercial non real estate Rate modification 1 49 49 — — — Term extension — — — 3 2,879 2,879 Payment modification 1 70 70 1 50 50 Bankruptcy — — — — — — Other 3 3,849 3,849 — — — Total commercial non real estate 5 3,968 3,968 4 2,929 2,929 Agriculture Rate modification — — — — — — Term extension 5 4,941 4,941 — — — Payment modification 4 989 989 — — — Bankruptcy — — — — — — Other — — — — — — Total agriculture 9 5,930 5,930 — — — Consumer Rate modification — — — — — — Term extension — — — — — — Payment modification — — — — — — Bankruptcy — — — 1 6 6 Other — — — — — — Total consumer — — — 1 6 6 Total accruing 17 $ 16,612 $ 16,612 13 $ 7,219 $ 7,129 Change in recorded investment due to principal paydown at time of modification — $ — $ — — $ — $ — Change in recorded investment due to chargeoffs at time of modification — $ — $ — 1 $ 90 $ — The following table presents a summary of all accruing loans restructured in TDRs during the six months ended March 31, 2016 and 2015 , respectively: Six Months Ended March 31, 2016 2015 Recorded Investment Recorded Investment ($ in thousands) Number Pre- Post- Number Pre- Post- Residential real estate Rate modification — $ — $ — 1 $ 15 $ 15 Term extension — — — — — — Payment modification — — — — — — Bankruptcy — — — — — — Other — — — 1 21 21 Total residential real estate — — — 2 36 36 Commercial real estate Rate modification — — — — — — Term extension 2 1,898 1,898 1 90 — Payment modification — — — 6 22,542 22,542 Bankruptcy — — — 1 498 498 Other 3 6,714 6,714 — — — Total commercial real estate 5 8,612 8,612 8 23,130 23,040 Commercial non real estate Rate modification 1 49 49 1 32 32 Term extension 1 58 58 3 2,879 2,879 Payment modification 1 70 70 2 1,874 1,874 Bankruptcy — — — — — — Other 3 3,849 3,849 — — — Total commercial non real estate 6 4,026 4,026 6 4,785 4,785 Agriculture Rate modification — — — — — — Term extension 13 26,914 26,914 — — — Payment modification 4 989 989 — — — Bankruptcy — — — — — — Other — — — — — — Total agriculture 17 27,903 27,903 — — — Consumer Rate modification — — — — — — Term extension — — — — — — Payment modification — — — — — — Bankruptcy — — — 1 6 6 Other — — — — — — Total consumer — — — 1 6 6 Total accruing 28 $ 40,541 $ 40,541 17 $ 27,957 $ 27,867 Change in recorded investment due to principal paydown at time of modification — $ — $ — — $ — $ — Change in recorded investment due to chargeoffs at time of modification — $ — $ — 1 $ 90 $ — The following table presents a summary of all non-accruing loans restructured in TDRs during the three months ended March 31, 2016 and 2015 : Three Months Ended March 31, 2016 2015 Recorded Investment Recorded Investment ($ in thousands) Number Pre- Post- Number Pre- Post- Residential real estate Rate modification — $ — $ — 2 $ 104 $ 104 Term extension — — — 1 77 77 Payment modification — — — — — — Bankruptcy — — — 1 43 43 Other — — — — — — Total residential real estate — — — 4 224 224 Commercial real estate Rate modification — — — — — — Term extension — — — — — — Payment modification — — — — — — Bankruptcy — — — — — — Other — — — — — — Total commercial real estate — — — — — — Commercial Non Real Estate Rate modification — — — — — — Term extension — — — 4 217 217 Payment modification 1 364 364 — — — Bankruptcy — — — — — — Other — — — — — — Total commercial non real estate 1 364 364 4 217 217 Agriculture Rate modification — — — — — — Term extension — — — — — — Payment modification — — — — — — Bankruptcy — — — — — — Other — — — — — — Total agriculture — — — — — — Consumer Rate modification — — — — — — Term extension — — — 1 1 1 Payment modification — — — — — — Bankruptcy 1 8 8 — — — Other — — — — — — Total consumer 1 8 8 1 1 1 Total non-accruing 2 $ 372 $ 372 9 $ 442 $ 442 Change in recorded investment due to principal paydown at time of modification — $ — $ — — $ — $ — Change in recorded investment due to chargeoffs at time of modification — $ — $ — — $ — $ — The following table presents a summary of all non-accruing loans restructured in TDRs during the six months ended March 31, 2016 and 2015 : Six Months Ended March 31, 2016 2015 Recorded Investment Recorded Investment ($ in thousands) Number Pre- Post- Number Pre- Post- Residential real estate Rate modification — $ — $ — 2 $ 104 $ 104 Term extension — — — 1 77 77 Payment modification 1 187 187 — — — Bankruptcy — — — 1 43 43 Other — — — — — — Total residential real estate 1 187 187 4 224 224 Commercial real estate Rate modification — — — — — — Term extension — — — — — — Payment modification — — — — — — Bankruptcy — — — — — — Other — — — — — — Total commercial real estate — — — — — — Commercial Non Real Estate Rate modification — — — — — — Term extension — — — 4 217 217 Payment modification 2 760 760 — — — Bankruptcy — — — — — — Other — — — — — — Total commercial non real estate 2 760 760 4 217 217 Agriculture Rate modification — — — — — — Term extension — — — — — — Payment modification — — — — — — Bankruptcy — — — — — — Other — — — — — — Total agriculture — — — — — — Consumer Rate modification — — — — — — Term extension — — — 1 1 1 Payment modification — — — — — — Bankruptcy 1 8 8 — — — Other — — — — — — Total consumer 1 8 8 1 1 1 Total non-accruing 4 $ 955 $ 955 9 $ 442 $ 442 Change in recorded investment due to principal paydown at time of modification — $ — $ — — $ — $ — Change in recorded investment due to chargeoffs at time of modification — $ — $ — — $ — $ — The tables below represent defaults on loans that were first modified during the respective past 12 months, that became 90 days or more delinquent or were charged-off during the three and six months ended March 31, 2016 and 2015 , respectively. Three Months Ended Six Months Ended 2016 2015 2016 2015 ($ in thousands) Number of Recorded Number of Recorded Number of Recorded Number of Recorded Residential real estate 1 $ — 4 $ 107 1 $ — 10 $ 629 Commercial real estate — — — — — — — — Commercial non real estate — — — — 1 364 1 95 Agriculture 2 — — — 2 — 1 15 Consumer — — — — 1 8 — — Total 3 $ — 4 $ 107 5 $ 372 12 $ 739 The majority of loans that were modified and subsequently became 90 days or more delinquent have remained on nonaccrual status since the time of modification. For the three and six months ended March 31, 2016 and 2015 , there were no significant loans removed from TDR status as they were restructured at market terms and are performing.

Allowance for Loan Losses

Allowance for Loan Losses	6 Months Ended
	Mar. 31, 2016
Receivables [Abstract]
Allowance for Loan Losses	Allowance for Loan Losses The following tables presents the Company’s allowance for loan losses roll forward for the three and six months ended March 31, 2016 and 2015 . Three Months Ended March 31, 2016 Residential Commercial Commercial Agriculture Consumer Other Total Beginning balance January 1, 2016 $ 7,798 $ 19,405 $ 17,160 $ 15,473 $ 341 $ 951 $ 61,128 Charge-offs (506 ) (744 ) (212 ) (1,113 ) (98 ) (597 ) (3,270 ) Recoveries 295 409 235 77 45 367 1,428 Provision 1,218 1,893 (4,552 ) 3,886 48 206 2,699 (Improvement) impairment of (9 ) (59 ) — — — — (68 ) Ending balance March 31, 2016 $ 8,796 $ 20,904 $ 12,631 $ 18,323 $ 336 $ 927 $ 61,917 Three Months Ended March 31, 2015 Residential Commercial Commercial Agriculture Consumer Other Total Beginning balance January 1, 2015 $ 7,567 $ 17,722 $ 14,625 $ 10,920 $ 201 $ 785 $ 51,820 Charge-offs (63 ) (1,570 ) (8,440 ) (27 ) (19 ) (403 ) (10,522 ) Recoveries 70 26 983 22 23 325 1,449 Provision 160 (389 ) 8,789 1,307 (17 ) 120 9,970 (Improvement) impairment of (239 ) (53 ) — — 1 — (291 ) Ending balance March 31, 2015 $ 7,495 $ 15,736 $ 15,957 $ 12,222 $ 189 $ 827 $ 52,426 Six Months Ended March 31, 2016 Residential Commercial Commercial Agriculture Consumer Other Total Beginning balance October 1, $ 8,025 $ 18,014 $ 15,996 $ 13,952 $ 348 $ 865 $ 57,200 Charge-offs (702 ) (772 ) (257 ) (1,124 ) (146 ) (997 ) (3,998 ) Recoveries 339 491 639 124 70 532 2,195 Provision 1,240 3,260 (3,677 ) 5,371 64 527 6,785 (Impairment) improvement of (106 ) (89 ) (70 ) — — — (265 ) Ending balance March 31, 2016 $ 8,796 $ 20,904 $ 12,631 $ 18,323 $ 336 $ 927 $ 61,917 Six Months Ended March 31, 2015 Residential Commercial Commercial Agriculture Consumer Other Total Beginning balance October 1, $ 8,342 $ 16,884 $ 10,550 $ 10,655 $ 264 $ 823 $ 47,518 Charge-offs (120 ) (1,652 ) (8,524 ) (27 ) (57 ) (831 ) (11,211 ) Recoveries 113 95 2,143 79 47 644 3,121 Provision (190 ) 346 11,788 1,515 (41 ) 191 13,609 (Impairment) improvement of (650 ) 63 — — (24 ) — (611 ) Ending balance March 31, 2015 $ 7,495 $ 15,736 $ 15,957 $ 12,222 $ 189 $ 827 $ 52,426 The following tables provide details regarding the allowance for loan and lease losses and balance by type of allowance. These tables (in thousands) are presented net of unamortized discount on acquired loans and excludes loans of $1.17 billion measured at fair value (and the associated credit mark embedded within the carrying value of these loans) with changes in fair value reported in earnings, loans held for sale of $5.9 million , and guaranteed loans of $129.8 million for March 31, 2016 and loans measured at fair value with changes in fair value reported in earnings of $1.12 billion , loans held for sale of $9.9 million , and guaranteed loans of $105.0 million for September 30, 2015 . As of March 31, 2016 Residential Commercial Commercial Agriculture Consumer Other Total Allowance for loan losses Individually evaluated for impairment $ 3,731 $ 7,293 $ 5,932 $ 6,963 $ 56 $ — $ 23,975 Collectively evaluated for impairment 3,547 12,618 6,699 11,360 280 927 35,431 Loans acquired with deteriorated credit quality 1,518 993 — — — — 2,511 Total allowance $ 8,796 $ 20,904 $ 12,631 $ 18,323 $ 336 $ 927 $ 61,917 Financing Receivables Individually evaluated for impairment $ 12,487 $ 50,495 $ 33,374 $ 92,657 $ 261 $ — $ 189,274 Collectively evaluated for impairment 806,809 2,600,323 1,016,396 1,450,270 63,136 39,510 5,976,444 Loans acquired with deteriorated credit quality 72,778 18,591 2,130 1,480 1,050 — 96,029 Loans Outstanding $ 892,074 $ 2,669,409 $ 1,051,900 $ 1,544,407 $ 64,447 $ 39,510 $ 6,261,747 As of September 30, 2015 Residential Commercial Commercial Agriculture Consumer Other Total Allowance for loan losses Individually evaluated for impairment $ 2,783 $ 4,585 $ 5,624 $ 3,950 $ 50 $ — $ 16,992 Collectively evaluated for impairment 3,618 12,347 10,302 10,002 298 865 37,432 Loans acquired with deteriorated credit quality 1,624 1,082 70 — — — 2,776 Total allowance $ 8,025 $ 18,014 $ 15,996 $ 13,952 $ 348 $ 865 $ 57,200 Financing Receivables Individually evaluated for impairment $ 13,106 $ 49,794 $ 62,158 $ 44,253 $ 193 $ — $ 169,504 Collectively evaluated for impairment 806,912 2,385,636 1,056,806 1,461,230 71,549 38,371 5,820,504 Loans acquired with deteriorated credit quality 82,189 20,710 2,759 1,538 1,271 — 108,467 Loans Outstanding $ 902,207 $ 2,456,140 $ 1,121,723 $ 1,507,021 $ 73,013 $ 38,371 $ 6,098,475 The Company maintains an ALL for acquired loans accounted for under ASC 310-30 as a result of impairment to loan pools arising from the periodic re-valuation of these loans. Any impairment in the individual pool is generally recognized in the current period as provision for loan losses. Any improvement in the estimated cash flows, is generally not recognized immediately, but is instead reflected as an adjustment to the related loan pools yield on a prospective basis once any previously recorded impairment has been recaptured. The ALL for loans acquired with deteriorated credit quality (ASC 310-30 loans) totaled $2.5 million at March 31, 2016 , compared to $2.8 million at September 30, 2015 . During the three and six month period ended March 31, 2016 , loan pools accounted for under ASC 310-30 had a net reversal of provision of $0.1 million and $0.3 million , respectively, as a result of increases in expected cash flows. Net provision reversals for the three and six month period ended March 31, 2015 totaled $0.3 million and $0.6 million , and were driven a result of increases in expected cash flows in the residential real estate pool. For acquired loans not accounted for under ASC 310-20 (purchased non-credit impaired), the Company utilizes specific and collective reserve calculation methods similar to originated loans. The required ALL for these loans is included in the individually evaluated for impairment bucket of the ALL if the loan is rated substandard or worse, and in the collectively evaluated for impairment bucket for pass rated loans. The reserve for unfunded loan commitments was $0.4 million at both March 31, 2016 and September 30, 2015 and is recorded in other liabilities on the consolidated balance sheets.

Accounting for Certain Loans Ac

Accounting for Certain Loans Acquired with Deteriorated Credit Quality	6 Months Ended
	Mar. 31, 2016
Receivables [Abstract]
Accounting for Certain Loans Acquired with Deteriorated Credit Quality	Accounting for Certain Loans Acquired with Deteriorated Credit Quality In June 2010 , the Company acquired certain loans that had deteriorated credit quality. Loan accounting specific to these purchased credit impaired loans addresses differences between contractual cash flows expected to be collected from the initial investment in loans if those differences are attributable, at least in part, to credit quality. Several factors were considered when evaluating whether a loan was considered a purchased credit impaired loan, including the delinquency status of the loan, updated borrower credit status, geographic information, and updated loan-to-values (“LTV”). U.S. GAAP allows purchasers to aggregate purchased credit impaired loans acquired in the same fiscal quarter in one or more pools, provided that the loans have common risk characteristics. A pool is then accounted for as a single asset with a single composite interest rate and an aggregate expectation of cash flows. Loan pools are periodically reassessed to determine expected cash flows. In determining the expected cash flows, the timing of cash flows and prepayment assumptions for smaller, homogeneous loans are based on statistical models that take into account factors such as the loan interest rate, credit profile of the borrowers, the years in which the loans were originated, and whether the loans are fixed or variable rate loans. Prepayments may be assumed on large individual loans that consider similar prepayment factors listed above for smaller homogeneous loans. The re-assessment of purchased credit impaired loans resulted in the following changes in the accretable yield during the three and six months ended March 31, 2016 and 2015 (in thousands): Three Months Ended Six Months Ended 2016 2015 2016 2015 Balance at beginning of period $ 41,882 $ 46,342 $ 44,489 $ 50,889 Accretion (2,261 ) (3,222 ) (4,590 ) (8,009 ) Reclassification from (to) nonaccretable difference 222 311 (56 ) 631 Disposals — — — (80 ) Balance at end of period $ 39,843 $ 43,431 $ 39,843 $ 43,431 The reclassification from nonaccretable difference noted in the table above represents instances where specific pools of loans are expected to perform better over the remaining lives of the loans than expected at the prior re-assessment date. The reclassification to nonaccretable difference noted in the table above represents instances where specific pools of loans are estimated to have a shortfall in the expected future cash flows compared to the contractual cash flows at the prior re-assessment date. The following table provides purchased credit impaired loans at March 31, 2016 and September 30, 2015 (in thousands): March 31, 2016 September 30, 2015 Outstanding 1 Recorded 2 Carrying 3 Outstanding 1 Recorded 2 Carrying 3 Residential real estate $ 83,921 $ 72,778 $ 71,260 $ 93,979 $ 82,189 $ 80,565 Commercial real estate 94,831 18,591 17,598 97,302 20,710 19,628 Commercial non real estate 8,957 2,130 2,130 10,387 2,759 2,689 Agriculture 1,481 1,480 1,480 1,538 1,538 1,538 Consumer 1,150 1,050 1,050 1,368 1,271 1,271 Total lending $ 190,340 $ 96,029 $ 93,518 $ 204,574 $ 108,467 $ 105,691 1 Represents the legal balance of loans acquired with deteriorated credit quality. 2 Represents the book balance of loans acquired with deteriorated credit quality. 3 Represents the book balance of loans acquired with deteriorated credit quality net of the related allowance for loan losses. Due to improved cash flows of the purchased credit impaired loans, the reductions to allowance recognized on previous impairments were $0.1 million and $0.4 million for the three months ended March 31, 2016 and 2015 , respectively and $0.3 million and $0.9 million for the six months ended March 31, 2016 and 2015 , respectively.

FDIC Indemnification Asset

FDIC Indemnification Asset	6 Months Ended
	Mar. 31, 2016
Banking and Thrift [Abstract]
FDIC Indemnification Asset	FDIC Indemnification Asset Under the terms of the purchase and assumption agreement with the FDIC with regard to the TierOne Bank acquisition, the Company is reimbursed for a portion of the losses incurred on covered assets. As covered assets are resolved, whether it be through repayment, short sale of the underlying collateral, the foreclosure on or sale of collateral, or the sale or charge-off of loans or OREO, any differences between the carrying value of the covered assets versus the payments received during the resolution process, that are reimbursable by the FDIC, are recognized as reductions in the FDIC indemnification asset. Any gains or losses realized from the resolution of covered assets reduce or increase, respectively, the amount recoverable from the FDIC. The following table represents a summary of the activity related to the FDIC indemnification asset for the three and six months ended March 31, 2016 and 2015 (in thousands): Three Months Ended Six Months Ended 2016 2015 2016 2015 Balance at beginning of period $ 13,185 $ 22,162 $ 14,722 $ 26,678 Amortization (895 ) (2,060 ) (1,927 ) (4,593 ) Changes in expected reimbursements from FDIC for changes in expected credit losses 1 2 (127 ) (190 ) Changes in reimbursable expenses (78 ) (207 ) (427 ) (363 ) Payments (reimbursements) of covered losses from the FDIC 662 (2 ) 634 (1,637 ) Balance at end of period $ 12,875 $ 19,895 $ 12,875 $ 19,895 The loss claims filed are subject to review, approval, and annual audits by the FDIC or its assigned agents for compliance with the terms in the loss sharing agreements. The non-commerical loss share agreement ends June 4, 2020.

Derivative Financial Instrument

Derivative Financial Instruments	6 Months Ended
	Mar. 31, 2016
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Financial Instruments	Derivative Financial Instruments In the normal course of business, the Company uses interest rate swaps to manage its interest rate risk and market risk in accommodating the needs of its customers. Also, the Company enters into interest rate lock commitments on mortgage loans to be held for sale, with corresponding forward sales contracts related to these interest rate lock commitments. Derivative instruments are recognized as either assets or liabilities in the accompanying consolidated financial statements and are measured at fair value. The following table summarizes the notional amounts and estimated fair values of the Company’s derivative instruments at March 31, 2016 and September 30, 2015 (in thousands). March 31, 2016 Notional Balance Sheet Positive Fair Negative Fair Derivatives not designated as hedging instruments: Interest rate swaps $ 1,094,357 Liabilities $ 10 $ (74,155 ) Mortgage loan commitments 32,556 Assets 52 — Mortgage loan forward sale contracts 34,757 Liabilities — (52 ) September 30, 2015 Notional Balance Sheet Positive Fair Negative Fair Derivatives not designated as hedging instruments: Interest rate swaps $ 1,087,505 Liabilities $ 41 $ (53,559 ) Mortgage loan commitments 30,196 Assets 95 — Mortgage loan forward sale contracts 36,655 Liabilities — (95 ) As with any financial instrument, derivative financial instruments have inherent risk including adverse changes in interest rates. The Company’s exposure to derivative credit risk is defined as the possibility of sustaining a loss due to the failure of the counterparty to perform in accordance with the terms of the contract. Credit risks associated with interest rate swaps are similar to those relating to traditional on-balance sheet financial instruments. The Company manages interest rate swap credit risk with the same standards and procedures applied to its commercial lending activities. Amounts due from swap counterparties to reclaim cash collateral under the interest rate swap master netting arrangements have not been offset against the derivative balances. Credit-risk-related contingent features The Company has agreements with its derivative counterparties that contain a provision where if the Company fails to maintain its status as a well/adequately capitalized institution, then the counterparty has the right to terminate the derivative positions and the Company would be required to settle its obligations under the agreements. As of March 31, 2016 , the termination value of derivatives in a net liability position related to these agreements was $77.1 million which includes accrued interest but excludes any adjustment for nonperformance risk. The Company has minimum collateral posting thresholds with its derivative counterparties and as of March 31, 2016 , the Company had posted $86.1 million in eligible collateral. The effect of derivatives on the consolidated statements of comprehensive income for the three and six months ended March 31, 2016 and 2015 (in thousands) was as follows: Amount of Gain (Loss) Recognized in Income Three Months Ended Six Months Ended Location of 2016 2015 2016 2015 Derivatives not designated as hedging instruments: Interest rate swaps Noninterest income $ (40,893 ) $ (21,698 ) $ (31,454 ) $ (46,303 ) Mortgage loan commitments Noninterest income 76 13 52 27 Mortgage loan forward sale contracts Noninterest income (76 ) (13 ) (52 ) (27 ) Netting of Derivatives The Company has various financial assets and financial liabilities that are subject to enforceable master netting agreements or similar agreements. The Company has entered into an ISDA master netting arrangement with various swap counterparties. Under the terms of the master netting arrangements, all transactions between the Company and the counterparty constitute a single business relationship such that in the event of default, the non-defaulting party is entitled to set off claims and apply property held by that party in respect of any transaction against obligations owed. Any payments, deliveries, or other transfers may be applied against each other and netted. The following tables (in thousands) present the Company's total gross derivative assets and liabilities at March 31, 2016 and September 30, 2015 , which are adjusted on an aggregate basis, where applicable, to take into consideration the effects of legally enforceable master netting agreements for the net reported amount in the consolidated balance sheets. These amounts are offset on the consolidated balance sheets. Gross Amount Net Amount Held/Pledged 1 Net March 31, 2016 Derivative financial assets: Derivatives subject to master netting arrangement or similar arrangement $ 10 $ (10 ) $ — $ — $ — Derivative financial liabilities: Derivatives subject to master netting arrangement or similar arrangement (74,155 ) 10 (74,145 ) 74,145 — Total derivative financial liabilities $ (74,145 ) $ — $ (74,145 ) $ 74,145 $ — 1 The actual amount of collateral exceeds the fair value exposure, at the individual counterparty level, as of the date presented. Gross Amount Net Amount Held/Pledged Net September 30, 2015 Derivative financial assets: Derivatives subject to master netting arrangement or similar arrangement $ 41 $ (41 ) $ — $ — $ — Derivative financial liabilities: Derivatives subject to master netting arrangement or similar arrangement (53,559 ) 41 (53,518 ) 53,518 — Total derivative financial liabilities $ (53,518 ) $ — $ (53,518 ) $ 53,518 $ —

The Fair Value Option For Certa

The Fair Value Option For Certain Loans	6 Months Ended
	Mar. 31, 2016
Fair Value Disclosures [Abstract]
The Fair Value Option For Certain Loans	The Fair Value Option For Certain Loans The Company has elected to measure certain long-term loans and written loan commitments at fair value to assist in managing the interest rate risk for longer-term loans. This fair value option was elected upon the origination of these loans. Interest income is recognized in the same manner as interest on non-fair value loans. See Note 15 for additional disclosures regarding the fair value of the fair value option loans and written loan commitments. Long-term loans and written loan commitments for which the fair value option has been elected had a net favorable difference between the aggregate fair value and the aggregate unpaid loan principal balance and written loan commitment amount of approximately $68.8 million and $47.8 million at March 31, 2016 and September 30, 2015 , respectively. The total unpaid principal balance of these long-term loans was approximately $1.09 billion and $1.07 billion at March 31, 2016 and September 30, 2015 , respectively. The fair value of these loans and written loan commitments is included in total loans in the consolidated balance sheets and are grouped with commercial non real estate, commercial real estate, and agricultural loans in Note 4. The fair value of these written loan commitments was not material at March 31, 2016 and September 30, 2015 , respectively. As of March 31, 2016 and September 30, 2015 , there were $0.0 million and $1.5 million , respectively, of the noted loans which were greater than 90 days past due or in nonaccrual status. Changes in fair value for items for which the fair value option has been elected and the line items in which these changes are reported within the consolidated statements of comprehensive income are as follows for the three and six months ended March 31, 2016 and 2015 (in thousands): For the Three Months Ended For the Six Months Ended March 31, 2016 March 31, 2015 March 31, 2016 March 31, 2015 Noninterest Total Changes Noninterest Total Changes Noninterest Total Changes Noninterest Total Changes Long-term loans and written loan commitments $ 35,956 $ 35,956 $ 15,208 $ 15,208 $ 21,055 $ 21,055 $ 32,308 $ 32,308 For long-term loans and written loan commitments, $(0.4) million and $(1.2) million for the three months ended March 31, 2016 and 2015 , respectively, and $(0.2) million and $0.5 million for the six months ended March 31, 2016 and 2015 , respectively, of the total change in fair value is attributable to changes in specific credit risk. The gains or losses attributable to changes in instrument-specific credit risk were determined based on an assessment of existing market conditions and credit quality of the underlying loan for the specific portfolio of loans.

Core Deposits and Other Intangi

Core Deposits and Other Intangibles	6 Months Ended
	Mar. 31, 2016
Goodwill and Intangible Assets Disclosure [Abstract]
Core Deposits and Other Intangibles	Core Deposits and Other Intangibles A summary of intangible assets subject to amortization is as follows (in thousands): Core Deposit Brand Customer Total As of March 31, 2016 Gross carrying amount $ 92,679 $ 8,464 $ 16,089 $ 117,232 Accumulated amortization (92,260 ) (4,418 ) (14,852 ) (111,530 ) Net intangible assets $ 419 $ 4,046 $ 1,237 $ 5,702 As of September 30, 2015 Gross carrying amount $ 92,679 $ 8,464 $ 16,089 $ 117,232 Accumulated amortization (92,073 ) (4,136 ) (13,904 ) (110,113 ) Net intangible assets $ 606 $ 4,328 $ 2,185 $ 7,119 Amortization expense of intangible assets was $0.7 million and $2.3 million for the three months ended March 31, 2016 and 2015 , respectively, and $1.4 million and $4.6 million for the six months ended March 31, 2016 and 2015 , respectively. The estimated amortization expense of intangible assets assumes no activities, such as acquisitions, which would result in additional amortizable intangible assets. Estimated amortization expense of intangible assets in subsequent fiscal years is as follows (in thousands): Remaining in 2016 $ 1,405 2017 1,097 2018 564 2019 564 2020 564 2021 and thereafter 1,508 Total $ 5,702

Securities Sold Under Agreement

Securities Sold Under Agreements to Repurchase	6 Months Ended
	Mar. 31, 2016
Federal Funds Purchased and Securities Sold under Agreements to Repurchase [Abstract]
Securities Sold Under Agreements to Repurchase	Securities Sold Under Agreements to Repurchase Securities sold under agreements to repurchase generally mature overnight following the transaction date. Securities underlying the agreements had an amortized cost of approximately $156.6 million and $180.6 million and fair value of approximately $156.7 million and $181.6 million at March 31, 2016 and September 30, 2015 , respectively. In most cases, the Company over-collateralizes the repurchase agreements at 102% of total funds borrowed to protect the purchaser from changes in market value. Additionally, the Company utilizes held-in-custody procedures to ensure the securities sold under repurchase agreements are unencumbered. The following tables present the gross obligation by the class of collateral pledged and the remaining contractual maturity of the agreements at March 31, 2016 and September 30, 2015 (in thousands). March 31, 2016 Remaining Contractual Maturity of the Agreements Overnight and Continuous Up to 30 Days 30-90 Days Greater than 90 Days Total Repurchase agreements US Treasury and agency $ — $ — $ — $ — $ — Mortgage-backed securities 143,329 — — 2,944 146,273 Total repurchase agreements $ 143,329 $ — $ — $ 2,944 $ 146,273 September 30, 2015 Remaining Contractual Maturity of the Agreements Overnight and Continuous Up to 30 Days 30-90 Days Greater than 90 Days Total Repurchase agreements US Treasury and agency $ 64,252 $ — $ — $ — $ 64,252 Mortgage-backed securities 118,147 — — 2,872 121,019 Total repurchase agreements $ 182,399 $ — $ — $ 2,872 $ 185,271

FHLB Advances and Other Borrowi

FHLB Advances and Other Borrowings	6 Months Ended
	Mar. 31, 2016
Federal Home Loan Banks [Abstract]
FHLB Advances and Other Borrowings	FHLB Advances and Other Borrowings FHLB advances and other borrowings consist of the following at March 31, 2016 and September 30, 2015 (in thousands): March 31, 2016 September 30, 2015 Notes payable to Federal Home Loan Bank (FHLB), interest rates from 0.43% to 3.66% and maturity dates from April 2016 to July 2023, collateralized by real estate loans and FHLB stock, with various call dates at the option of the FHLB $ 370,000 $ 581,000 The Company has a $10.0 million revolving line of credit with Wells Fargo, which expires on July 30, 2016 . The line of credit has an interest rate of 1 Mo LIBOR plus 200 basis points, with interest payable monthly. There is also an unused line fee of .20% on the unused portion which is payable quarterly. The interest rate was 2.44% at March 31, 2016 . There were no outstanding advances on this line of credit at March 31, 2016 and September 30, 2015 . As of March 31, 2016 , based on its Federal Home Loan Bank stock holdings, the combined aggregate additional borrowing capacity of the Company with the Federal Home Loan Bank was $976.8 million . Principal balances of loans pledged to the Federal Home Loan Bank to collateralize notes payable totaled $2.27 billion and $2.29 billion at March 31, 2016 and September 30, 2015 , respectively. As of March 31, 2016 , FHLB advances and other borrowings are due or callable (whichever is earlier) in subsequent fiscal years as follows (in thousands): Remaining in 2016 $ 60,000 2017 25,000 2018 25,000 2019 — 2020 — 2021 and thereafter 260,000 Total $ 370,000

Profit-Sharing Plan

Profit-Sharing Plan	6 Months Ended
	Mar. 31, 2016
Employee Service Share-based Compensation, Aggregate Disclosures [Abstract]
Profit-Sharing Plan	Profit-Sharing Plan The Company participates in a multiple employer 401(k) profit sharing plan (the Plan). All employees are eligible to participate, beginning with the first day of the month coincident with or immediately following the completion of one year of service and having reached the age of 21 . In addition to employee contributions, the Company may contribute discretionary amounts for eligible participants. Contribution rates for participating employees must be equal. The Company contributed $0.6 million and $0.5 million to the Plan for the three months ended March 31, 2016 and 2015 , respectively and $2.0 million and $1.8 million for the six months ended March 31, 2016 and 2015 , respectively.

Stock-Based Compensation

Stock-Based Compensation	6 Months Ended
	Mar. 31, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-Based Compensation	Stock-Based Compensation On September 26, 2014, the Board of Directors adopted, and on October 10, 2014, NAB, at that time our controlling shareholder, approved the Great Western Bancorp, Inc. 2014 Omnibus Incentive Compensation Plan (the “2014 Plan”), the Great Western Bancorp, Inc. 2014 Non-Employee Director Plan (the “2014 Director Plan”), and the Great Western Bancorp, Inc. Executive Incentive Compensation Plan (the “Bonus Plan”), collectively ("the Plans"), which provide for the issuance of restricted share units and performance based share units to certain officers, employees and directors of the Company. The Plans were primarily established to enhance the Company’s ability to attract, retain and motivate employees. The Company’s Board of Directors, the Compensation Committee of the Board of Directors ("Compensation Committee"), or executive management upon delegation of the Compensation Committee has exclusive authority to select the employees and others, including directors, to receive the awards and to establish the terms and conditions of each award made pursuant to the Company’s stock-based compensation plans. Stock units issued under the Company’s restricted and performance based stock plans may not be sold or otherwise transferred until the vesting period (typically 3 years) has been met and/or performance objectives have been obtained. During the vesting periods, participants do not have voting rights and dividends are accumulated until the time upon which the award vests. Upon specified events, as defined in the Plans, stock unit awards that have not vested and/or performance hurdles that have not been met will be forfeited. Based on the substantive terms of each award, restricted and performance-based awards are classified as equity awards and accounted for under the Treasury method. The fair value of equity-classified awards is based on the market price of the stock on the measurement date and is amortized as compensation expense on a straight-line basis over the vesting or performance period. Stock based compensation is recognized based on the number of awards that are ultimately expected to vest. Forfeitures are estimated based on historical turnover experience of qualified employees. For performance-based stock awards, an estimate is made of the number of shares expected to vest as a result of actual performance against the performance targets to determine the amount of compensation expense to be recognized. The estimate is reevaluated quarterly and total compensation expense is adjusted for any change in the current period. Stock-based compensation expense is included in salaries and employee benefits expense in the consolidated statements of comprehensive income. For the three months ended March 31, 2016 and 2015 , stock compensation expense was $0.7 million and $0.2 million , respectively. For the six months ended March 31, 2016 and 2015 , stock compensation expense was $1.8 million and $0.7 million , respectively. Related income tax benefits recognized were $0.3 million and $0.1 million for the three months ended March 31, 2016 and 2015 , respectively and $0.7 million and $0.3 million for the six months ended March 31, 2016 and 2015 , respectively. The following is a summary of the Plans’ restricted share and performance-based stock award activity as of March 31, 2016 and September 30, 2015 : March 31, 2016 September 30, 2015 Restricted Shares Common Shares Weighted-Average Common Shares Weighted-Average Restricted shares, beginning of fiscal year 80,446 $ 18.18 — $ — Granted 91,896 30.73 81,419 18.18 Vested and issued (25,526 ) 18.06 — — Forfeited (1,181 ) 24.69 (973 ) 18.00 Canceled — — — — Restricted shares, end of period 145,635 $ 26.07 80,446 $ 18.18 Vested, but not issuable at end of period 24,480 $ 26.14 12,221 $ 18.00 Performance Shares Performance shares, beginning of fiscal year 211,026 $ 18.00 — $ — Granted 43,371 30.78 221,294 18.00 Vested and issued (55 ) 18.00 — — Forfeited (4,236 ) 19.22 (10,268 ) 18.00 Canceled — — — — Performance shares, end of period 250,106 $ 20.20 211,026 $ 18.00 The number of performance shares granted is reflected in the above table at the 100% target performance level. The actual performance-based award payouts will vary based on the achievement of the pre-established targets and can range from 0% to 150% of the target amount. The outstanding number of performance shares reflected in the table represents the number of shares expected to be awarded based on estimated achievement of the goals as of March 31, 2016 . The maximum number of performance-based shares that could be issued if performance is attained at 150% of target based on the grants made to date was approximately 375,159 shares at March 31, 2016 . As of March 31, 2016 , there was $ 5.5 million of unrecognized compensation cost related to nonvested restricted stock awards expected to be recognized over a period of 2.7 years. The fair value of the vested, but not issued stock awards at March 31, 2016 , was $0.7 million .

Fair Value Measurements

Fair Value Measurements	6 Months Ended
	Mar. 31, 2016
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements The Company measures, monitors and discloses certain of its assets and liabilities on a fair value basis. Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. The fair value guidance also establishes a fair value hierarchy that requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. The guidance describes three levels of inputs that may be used to measure fair value are as follows: Level 1 Quoted prices in active markets for identical assets or liabilities Level 2 Observable inputs other than Level 1 prices, such as quoted prices for similar assets or liabilities; quoted prices in markets that are not active; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities Level 3 Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities Level 1 inputs are considered to be the most transparent and reliable and Level 3 inputs are considered to be the least transparent and reliable. The Company assumes the use of the principal market to conduct a transaction of each particular asset or liability being measured and then considers the assumptions that market participants would use when pricing the asset or liability. Whenever possible, the Company first looks for quoted prices for identical assets or liabilities in active markets (Level 1 inputs) to value each asset or liability. However, when inputs from identical assets or liabilities on active markets are not available, the Company utilizes market observable data for similar assets and liabilities. The Company maximizes the use of observable inputs and limits the use of unobservable inputs to occasions when observable inputs are not available. The need to use unobservable inputs generally results from the lack of market liquidity of the actual financial instrument or of the underlying collateral. Although in some instances, third party price indications may be available, limited trading activity can challenge the observability of these quotations. Assets and Liabilities Measured at Fair Value on a Recurring Basis Following is a description of the valuation methodologies and inputs used for assets and liabilities measured at fair value on a recurring basis and recognized in the accompanying consolidated balance sheets, as well as the general classification of such assets and liabilities pursuant to the valuation hierarchy. Securities Available for Sale Where quoted market prices are available in an active market, securities are classified within Level 1 of the valuation hierarchy. Level 1 securities include U.S. Treasury securities and U.S. Agency securities. If quoted market prices are not available, then fair values are estimated by using pricing models, quoted prices of securities with similar characteristics, or discounted cash flows and classified as Level 2 securities. Level 2 securities include agency mortgage-backed, states and political subdivisions, corporate debt, and other securities. Where Level 1 or Level 2 inputs are not available, securities are classified within Level 3 of the hierarchy. Interest Rate Swaps and Loans Interest rate swaps are valued by the Company's Swap Dealers using LIBOR rates. The fair value of loans accounted for under the fair value option represents the net carrying value of the loan, plus the equal and opposite amount of the value of the swap needed to hedge the interest rate risk and an adjustment for credit risk based on our assessment of existing market conditions for the specific portfolio of loans. This is used due to the strict prepayment penalties put in the loan terms to cover the cost of exiting the hedge of the loans in the case of early prepayment or termination. The adjustment for credit risk on loans accounted for under the fair value option is not significant to the overall fair value of the loans. The fair values estimated by the Company's Swap Dealers use interest rates that are observable or that can be corroborated by observable market data and, therefore, are classified within Level 2 of the valuation hierarchy. The Company is required to post cash collateral to swap counterparties for interest rate derivative contracts that are in a liability position, thus a credit risk adjustment on interest rate swaps is not warranted. The following table presents the fair value measurements of assets and liabilities recognized in the accompanying consolidated balance sheets measured at fair value on a recurring basis and the level within the fair value hierarchy in which the fair value measurements fall at March 31, 2016 and September 30, 2015 (in thousands): Fair Value Level 1 Level 2 Level 3 As of March 31, 2016 U.S. Treasury securities $ 230,837 $ 230,837 $ — $ — U.S. Agency securities 74,996 74,996 — — Mortgage-backed securities 1,015,350 — 1,015,350 — States and political subdivision securities 1,458 — — 1,458 Corporate debt securities 4,991 — 4,991 — Other 1,053 — 1,053 — Securities available for sale $ 1,328,685 $ 305,833 $ 1,021,394 $ 1,458 Derivatives-assets $ 52 $ 52 $ — Derivatives-liabilities 74,197 — 74,197 — Fair value loans and written loan commitments 1,165,660 — 1,165,660 — Fair Value Level 1 Level 2 Level 3 As of September 30, 2015 U.S. Treasury securities $ 254,797 $ 254,797 $ — $ — U.S. Agency securities 75,055 75,055 — — Mortgage-backed securities 989,600 — 989,600 — States and political subdivision securities 1,850 — 15 1,835 Corporate debt securities 4,983 — 4,983 — Other 1,042 — 1,042 — Securities available for sale $ 1,327,327 $ 329,852 $ 995,640 $ 1,835 Derivatives-assets $ 95 $ — $ 95 $ — Derivatives-liabilities 53,613 — 53,613 — Fair value loans and written loan commitments 1,118,687 — 1,118,687 — The following table presents the changes in Level 3 financial instruments for the three and six months ended March 31, 2016 and 2015 (in thousands): Other Securities Available for Sale Three months ended March 31, Six months ended March 31, 2016 2015 2016 2015 Balance, beginning of period $ 1,458 $ 1,958 $ 1,835 $ 2,029 Principal paydown — — (77 ) (71 ) Realized loss on securities — — (300 ) — Balance, end of period $ 1,458 $ 1,958 $ 1,458 $ 1,958 Assets and Liabilities Measured at Fair Value on a Nonrecurring Basis Following is a description of the valuation methodologies used for assets and liabilities measured at fair value on a nonrecurring basis and recognized in the accompanying consolidated balance sheets, as well as the general classification of such assets and liabilities pursuant to the valuation hierarchy. Impaired Loans (Collateral Dependent) Loans for which it is probable that the Company will not collect all principal and interest due according to contractual terms are measured for impairment. Allowable methods for estimating fair value include using the fair value of the collateral for collateral dependent loans or, where a loan is determined not to be collateral dependent, using the discounted cash flow method. If the impaired loan is identified as collateral dependent, then the fair value method of measuring the amount of the impairment is utilized. This method requires obtaining a current independent appraisal of the collateral and applying a discount factor, if necessary, to the appraised value and including costs to sell. Because many of these inputs are not observable, the measurements are classified as Level 3. Other Real Estate Owned (OREO) Other real estate owned consists of loan collateral that has been repossessed through foreclosure. This collateral is comprised of commercial and residential real estate. OREO is recorded initially at fair value of the collateral less estimated selling costs. Subsequent to foreclosure, valuations are updated periodically, and the assets may be marked down further to fair value less selling costs, reflecting a valuation allowance. Fair value measurements may be based upon appraisals, third-party price opinions, or internally developed pricing methods. These measurements are classified as Level 3. Mortgage Loans Held for Sale Fair value of mortgage loans held for sale is based on either quoted prices for the same or similar loans, or values obtained from third parties, or are estimated for portfolios of loans with similar financial characteristics and are therefore considered a Level 2 valuation. The following tables present the fair value measurement of assets and liabilities measured at fair value on a nonrecurring basis and the level within the fair value hierarchy in which the fair value measurements fall at March 31, 2016 and September 30, 2015 (in thousands): Fair Value Level 1 Level 2 Level 3 As of March 31, 2016 Other real estate owned $ 1,068 $ — $ — $ 1,068 Impaired loans 165,924 — — 165,924 Loans held for sale, at lower of cost or fair value 5,918 — 5,918 — As of September 30, 2015 Other real estate owned $ 8,826 $ — $ — $ 8,826 Impaired loans 153,318 — — 153,318 Loans held for sale, at lower of cost or fair value 9,867 — 9,867 — The valuation techniques and significant unobservable inputs used to measure Level 3 fair value measurements at March 31, 2016 were as follows (in thousands): Financial Fair Value of Assets / (Liabilities) at March 31, 2016 Valuation Unobservable Range Weighted Other real estate owned $ 1,068 Appraisal value Property specific adjustment N/A N/A Impaired loans $ 165,924 Appraisal value Property specific adjustment N/A N/A Disclosures about Fair Value of Financial Instruments For financial instruments that have quoted market prices, those quotes are used to determine fair value. Financial instruments that have no defined maturity, have a remaining maturity of 180 days or less, or reprice frequently to a market rate are assumed to have a fair value that approximates carrying value, after taking into consideration any applicable credit risk. If no market quotes are available, financial instruments are valued by discounting the expected cash flows using an estimated current market interest rate for the financial instrument. The short maturity of the Company’s assets and liabilities results in having a significant number of financial instruments whose fair value equals or closely approximates carrying value. Such financial instruments are reported in the following consolidated balance sheet categories: cash and due from banks, securities sold under agreements to repurchase, and accrued interest. Fair value estimates are based on existing on and off-balance sheet financial instruments without attempting to estimate the value of anticipated future business and the value of assets and liabilities that are not considered financial instruments. Significant assets and liabilities that are not considered financial instruments include premises and equipment, deferred income taxes, goodwill, and core deposit and other intangibles. In addition, the tax ramifications related to the realization of unrealized gains and losses can have a significant effect on fair value estimates and have not been considered in the estimates. Off-balance sheet instruments (commitments to extend credit and standby letters of credit) are generally short-term and at variable rates. Therefore, both the carrying amount and the estimated fair value associated with these instruments are immaterial. Fair values for balance sheet instruments as of March 31, 2016 and September 30, 2015 , are as follows (in thousands): March 31, 2016 September 30, 2015 Level in Carrying Fair Value Carrying Fair Value Assets Cash and due from banks Level 1 $ 174,401 $ 174,401 $ 237,770 $ 237,770 Loans, net excluding fair valued loans and loans Level 3 6,324,293 6,300,553 6,139,444 6,120,262 Accrued interest receivable Level 2 39,487 39,487 44,077 44,077 Federal Home Loan Bank stock Level 2 27,127 27,127 35,745 35,745 Liabilities Deposits Level 2 $ 7,712,729 $ 7,711,376 $ 7,387,065 $ 7,385,894 FHLB advances and other borrowings Level 2 370,000 373,559 581,000 584,261 Securities sold under repurchase agreements Level 2 146,273 146,273 185,271 185,271 Accrued interest payable Level 2 3,987 3,987 4,006 4,006 Subordinated debentures and subordinated notes payable Level 2 90,764 91,764 90,727 91,305 The following methods and assumptions were used in estimating the fair value of financial instruments that were not previously disclosed: Cash and cash due from banks: Due to the short term nature of cash and cash equivalents, the estimated fair value is equal to the carrying value and they are categorized as a Level 1 fair value measurement. Loans, net excluding fair valued loans and loans held for sale: The fair value of the loan portfolio is estimated using observable inputs including estimated cash flows, and discount rates based on interest rates currently being offered for loans with similar terms, to borrowers of similar credit quality. Loans held for investment are categorized as a Level 3 fair value measurement. Accrued interest receivable: Due to the nature of accrued interest receivable, the estimated fair value is equal to the carrying value and they are categorized as a Level 2 fair value measurement. Federal Home Loan Bank stock: The carrying amount of FHLB stock approximates its fair value as it can only be redeemed with the FHLB at par value. Federal Home Loan Bank stock has been categorized as a Level 2 fair value measurement. Deposits: The estimated fair value of deposits with no stated maturity, such as non-interest bearing demand deposits, savings, NOW, and money market accounts, is equal to the amount payable on demand. The fair value of interest-bearing time deposits is based on the discounted value of contractual cash flows of such deposits, taking into account the option for early withdrawal. The discount rate is estimated using the rates offered by the Company, at the respective measurement dates, for deposits of similar maturities. Deposits have been categorized as a Level 2 fair value measurement. FHLB advances and other borrowings: The fair value of FHLB advances and other borrowings is estimated using discounted cash flow analysis, based on current incremental borrowing rates for similar types of borrowing arrangements. In the absence of a reasonably precise methodology to determine the fair value of the credit agreement, carrying value has been used to represent fair value. FHLB advances and other borrowings have been categorized as a Level 2 fair value measurement. Securities sold under repurchase agreements: The Company’s repurchase agreements are overnight transactions that mature the day after the transaction, and as a result of this short-term nature, the estimated fair value equals the carrying value. Securities sold under repurchase agreements have been categorized as a Level 2 fair value measurement. Accrued interest payable: Due to the nature of accrued interest payable, the estimated fair value is equal to the carrying value and they are categorized as a Level 2 fair value measurement. Subordinated Debentures and Subordinated Notes Payable: The fair value of subordinated debentures and subordinated notes payable is estimated using discounted cash flow analysis, based on current incremental debt rates. Subordinated debentures and subordinated notes payable have been categorized as a Level 2 fair value measurement.

Earnings per Share

Earnings per Share	6 Months Ended
	Mar. 31, 2016
Earnings Per Share [Abstract]
Earnings per Share	Earnings per Share Basic earnings per common share is calculated by dividing net income available to common shareholders by the weighted average number of common shares outstanding during the period, excluding outstanding non-vested restricted stock awards. Diluted earnings per common share is calculated by dividing net income available to common shareholders by the weighted average number of common shares outstanding determined for the basic earnings per share calculation plus the dilutive effect of stock compensation using the treasury stock method. The following information was used in the computation of basic earnings per share (EPS) for the three and six months ended March 31, 2016 and 2015 (in thousands except share data). Three Months Ended Six Months Ended 2016 2015 2016 2015 Net income $ 30,674 $ 19,724 $ 61,135 $ 46,421 Weighted average common shares outstanding 55,269,557 57,898,335 55,261,634 57,897,059 Dilutive effect of stock based compensation 139,319 18,467 139,530 9,234 Weighted average common shares outstanding for diluted earnings per share calculation 55,408,876 57,916,802 55,401,164 57,906,293 Basic earnings per share $ 0.56 $ 0.34 $ 1.11 $ 0.80 Diluted earnings per share $ 0.55 $ 0.34 $ 1.10 $ 0.80 The Company had 36,696 and 30,909 shares of unvested performance stock as of March 31, 2016 and 2015 , respectively, that were not included in the computation of diluted earnings per common share because performance conditions for vesting had not been met. The Company had 174,415 and 152,827 shares of anti-dilutive stock awards outstanding as of March 31, 2016 and 2015 , respectively.

Nature of Operations and Summ25

Nature of Operations and Summary of Significant Policies (Policies)	6 Months Ended
	Mar. 31, 2016
Accounting Policies [Abstract]
Basis of Presentation	The accompanying unaudited consolidated interim financial statements have been prepared in accordance with accounting principles generally accepted in the United States (“U.S. GAAP”) and reflect all adjustments that are, in the opinion of management, necessary for the fair presentation of the financial position and results of operations for the periods presented. All such adjustments are of a normal recurring nature. Certain previously reported amounts have been reclassified to conform to the current presentation.
Principles of Consolidation	The accompanying unaudited consolidated financial statements include the accounts and results of operations of the Company and its subsidiaries after elimination of all significant intercompany accounts and transactions. The preparation of unaudited consolidated financial statements in conformity with U.S. GAAP requires management to make certain estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. Actual results could differ from these estimates.
Business Combinations	The Company accounts for business combinations under the acquisition method of accounting in accordance with ASC 805, “Business Combinations” (“ASC 805”). The Company recognizes the fair value of the assets acquired and liabilities assumed, immediately expenses transaction costs and accounts for restructuring plans separately from the business combination. There is no separate recognition of the acquired allowance for loan losses on the acquirer’s balance sheet as credit related factors are incorporated directly into the fair value of the loans recorded at the acquisition date. The excess of the cost of the acquisition over the fair value of the net tangible and intangible assets acquired is recorded as goodwill. Alternatively, a bargain purchase gain is recorded equal to the amount by which the fair value of assets purchased exceeds the fair value of liabilities assumed and consideration paid. Results of operations of the acquired business are included in the consolidated statements of comprehensive income from the effective date of acquisition.
Securities	The Company classifies securities upon purchase in one of three categories: trading, held-to-maturity, or available-for-sale. Debt and equity securities held for resale are classified as trading. Debt securities for which the Company has the ability and positive intent to hold until maturity are classified as held-to-maturity. All other securities are classified as available-for-sale as they may be sold prior to maturity in response to changes in the Company’s interest rate risk profile, funding needs, demand for collateralized deposits by public entities or other reasons. Held-to-maturity securities are stated at amortized cost, which represents actual cost adjusted for premium amortization and discount accretion. Available-for-sale securities are stated at fair value, with unrealized gains and losses, net of related taxes, included in stockholders’ equity as a component of accumulated other comprehensive income (loss). Trading securities are stated at fair value. Realized and unrealized gains and losses from sales and fair value adjustments of trading securities are included in other noninterest income in the consolidated statements of comprehensive income. Purchases and sales of securities are recognized on a trade date basis. The cost of securities sold is based on the specific identification method. Declines in the fair value of investment securities available for sale (with certain exceptions for debt securities noted below) that are deemed to be other-than-temporary are recognized in earnings as a realized loss, and a new cost basis for the securities is established. In evaluating other-than-temporary impairment, management considers the length of time and extent to which the fair value has been less than amortized cost, the financial condition and near-term prospects of the issuer, and the intent and ability of the Company to retain its investment in the issuer for a period of time sufficient to allow for any anticipated recovery in fair value in the near term. Declines in the fair value of debt securities below amortized cost are deemed to be other-than-temporary in circumstances where: (1) the Company has the intent to sell a security; (2) it is more likely than not that the Company will be required to sell the security before recovery of its amortized cost basis; or (3) the Company does not expect to recover the entire amortized cost basis of the security. If the Company intends to sell a security or if it is more likely than not that the Company will be required to sell the security before recovery, an other-than-temporary impairment loss is recognized in earnings equal to the difference between the security’s amortized cost basis and its fair value. If the Company does not intend to sell the security or it is not more likely than not that it will be required to sell the security before recovery, the other-than-temporary impairment write-down is separated into an amount representing credit loss, which is recognized in earnings, and an amount related to all other factors, which is recognized in accumulated other comprehensive income (loss). Interest and dividends, including amortization of premiums and accretion of discounts, are recognized as interest or dividend income when earned. Realized gains and losses on sales (using the specific identification method) and declines in value judged to be other- than-temporary are included in noninterest income in the consolidated statements of comprehensive income.
Loans	The Company’s accounting method for loans differs depending on whether the loans were originated or purchased and, for purchased loans, whether the loans were acquired at a discount related to evidence of credit deterioration since date of origination. Originated Loans Loans that management has the intent and ability to hold for the foreseeable future, or until maturity or pay-off, generally are reported at their outstanding principal balance, adjusted for charge-offs, the allowance for loan losses, and any unamortized deferred fees or costs. Other fees, not associated with originating a loan are recognized as fee income when earned. Interest income on loans is accrued daily on the outstanding balances. Accrual of interest is discontinued when management believes, after considering collection efforts and other factors, the borrower’s financial condition is such that collection of interest is doubtful, which is generally at 90 days past due. Generally, when loans are placed on nonaccrual status, interest receivable is reversed against interest income in the current period. Interest payments received thereafter are applied as a reduction to the remaining principal balance as long as concern exists as to the ultimate collection of the principal. Loans are removed from nonaccrual status when they become current as to both principal and interest and concern no longer exists as to the collectability of principal and interest. The Company has elected to measure certain long-term loans and written loan commitments at fair value to assist in managing interest rate risk for longer-term loans. Fair value loans are fixed-rate loans having original maturities of 5 years or greater (typically between 5 and 15 years ) to our business and agribusiness banking customers to assist them in facilitating their risk management strategies. The fair value option was elected upon the origination or acquisition of these loans and written loan commitments. Interest income is recognized in the same manner on loans reported at fair value as on non-fair value loans, except in regard to origination fees and costs which are recognized immediately upon closing. The changes in fair value of long-term loans and written loan commitments at fair value are reported in noninterest income. For loans held for sale, loan fees charged or received on origination, net of certain direct loan origination costs, are recognized in income when the related loan is sold. For loans held for investment, loan fees, net of certain direct loan origination costs, are deferred, and the net amount is amortized as an adjustment of the related loan’s yield. The Company is generally amortizing these amounts over the contractual lives of the loans. Commitment fees are recognized as income when received. The Company grants commercial, agricultural, consumer, residential real estate, and other loans to customers primarily in Arizona, Colorado, Iowa, Kansas, Missouri, Nebraska, and South Dakota. The amount of collateral obtained, if deemed necessary, is based on management’s credit evaluation of the borrower. Collateral held varies but includes accounts receivable, inventory, property and equipment, residential real estate, and income-producing commercial and agricultural properties. Government guarantees are also obtained for some loans, which reduces the Company’s risk of loss. Loans originated and intended for sale in the secondary market are carried at the lower of cost or fair value. Loans held for sale include fixed rate single-family residential mortgage loans under contract to be sold in the secondary market. In most cases, loans are carried at cost and sold within 45 days . These loans are sold with the mortgage servicing rights released. Under limited circumstances, buyers may have recourse to return a purchased loan to the Company. Recourse conditions may include early payment default, breach of representation or warranties, or documentation deficiencies. Fair value of loans held for sale is determined based on prevailing market prices for loans with similar characteristics, sale contract prices, or, for certain portfolios, discounted cash flow analysis. Declines in fair value below cost (and subsequent recoveries) are recognized in net gain on sale of loans. Deferred fees and costs related to these loans are not amortized but are recognized as part of the cost basis of the loan at the time it is sold. Gains or losses on sales are recognized upon delivery and included in net gain on sale of loans. Purchased Loans Loans acquired (non-impaired and impaired) in a business acquisition are recorded at their fair value at the acquisition date. Credit discounts are included in the determination of fair value; therefore, an allowance for loan losses is not recorded at the acquisition date. In determining the acquisition date fair value of purchased loans with evidence of credit deterioration (“purchased impaired loans”), and in subsequent accounting, the Company generally aggregates impaired purchased consumer and certain smaller balance impaired commercial loans into pools of loans with common risk characteristics, while accounting for larger-balance impaired commercial loans individually. Expected cash flows at the acquisition date in excess of the fair value of loans are recorded as interest income over the life of the loans using a level-yield method. Management estimates the cash flows expected to be collected at acquisition and at subsequent measurement dates using internal risk models, which incorporate the estimate of key assumptions, such as default rates, loss severity, and prepayment speeds. Subsequent to the acquisition date, decreases in cash flows over those expected at the acquisition date are recognized by recording an allowance for loan losses. Subsequent increases in cash flow over those expected at the acquisition date are recognized as reductions to allowance for loan losses to the extent impairment was previously recognized and thereafter as interest income prospectively. For purchased loans not deemed impaired at the acquisition date, the difference between the fair value and the unpaid principal balance of the loan at acquisition date is amortized or accreted to interest income using the effective interest method over the remaining period to contractual maturity. Credit Risk Management The Company’s strategy for credit risk management includes well-defined, centralized credit policies, uniform underwriting criteria and ongoing risk monitoring and review processes for all credit exposures. The strategy also emphasizes diversification on a geographic, industry, and customer level; regular credit examinations; and management reviews of loans exhibiting deterioration of credit quality. The credit risk management strategy also includes a credit risk assessment process that performs assessments of compliance with commercial and consumer credit policies, risk ratings, and other critical credit information. Loan decisions are documented with respect to the borrower’s business, purpose of the loan, evaluation of the repayment sources, and the associated risks, evaluation of collateral, covenants and monitoring requirements, and risk rating rationale. The Company categorizes its loan portfolio into six classes, which is the level at which it develops and documents a systematic methodology to determine the allowance for loan losses. The Company’s six loan portfolio classes are residential real estate, commercial real estate, commercial non real estate, agriculture, consumer and other lending. The residential real estate lending class includes loans made to consumer customers including residential mortgages, residential construction loans and home equity loans and lines. These loans are typically fixed rate loans secured by residential real estate. Home equity lines are revolving accounts giving the borrower the ability to draw and repay balances repeatedly, up to a maximum commitment, and are secured by residential real estate. Home equity lines typically have variable rate terms which are benchmarked to a prime rate. Historical loss history is the primary factor in determining the allowance for loan losses for the residential real estate lending class. Key risk characteristics relevant to residential real estate lending class loans primarily relate to the borrower’s capacity and willingness to repay and include unemployment rates and other economic factors, and customer payment history. These risk characteristics, among others, are reflected in the environmental factors considered in determining the allowance for loan losses. The commercial real estate lending class includes loans made to small and middle market businesses, including multifamily properties. Loans in this class are secured by commercial real estate. Historical loss history and updated loan-to-value information on collateral-dependent loans are the primary factors in determining the allowance for loan losses for the commercial real estate lending class. Key risk characteristics relevant to the commercial real estate lending class include the industry and geography of the borrower’s business, purpose of the loan, repayment sources, borrower’s debt capacity and financial performance, loan covenants, and nature of pledged collateral. We consider these risk characteristics in assigning risk ratings and estimating environmental factors considered in determining the allowance for loan losses. The commercial non real estate lending class includes loans made to small and middle market businesses, and loans made to public sector customers. Loans in this class are generally secured by business assets and guaranteed by owners; cashflows are most often our primary source of repayment. Historical loss history and updated loan-to-value information on collateral-dependent loans are the primary factors in determining the allowance for loan losses for the commercial non real estate lending class. Key risk characteristics relevant to the commercial non real estate lending class include the industry and geography of the borrower’s business, purpose of the loan, repayment sources, borrower’s debt capacity and financial performance, loan covenants, and nature of pledged collateral. We consider these risk characteristics in assigning risk ratings and estimating environmental factors considered in determining the allowance for loan losses. The agriculture lending class includes loans made to small and mid-size agricultural businesses and individuals. Loans in this class are generally secured by operating assets and guaranteed by owners; cashflows are most often our primary source of repayment. Historical loss history and updated loan-to-value information on collateral-dependent loans are the primary factors in determining the allowance for loan losses for the agriculture lending class. Key risk characteristics relevant to the agriculture lending class include the geography of the borrower’s operations, commodity prices and weather patterns, purpose of the loan, repayment sources, borrower’s debt capacity and financial performance, loan covenants, and nature of pledged collateral. We consider these risk characteristics in assigning risk ratings and estimating environmental factors considered in determining the allowance for loan losses. The consumer lending class includes loans made to consumer customers including loans secured by automobiles and other installment loans, and the other lending class includes credit card loans and unsecured revolving credit lines. Historical loss history is the primary factor in determining the allowance for loan losses for the consumer and other lending classes. Key risk characteristics relevant to loans in the consumer and other lending classes primarily relate to the borrower’s capacity and willingness to repay and include unemployment rates and other economic factors, and customer payment and overall credit history. These risk characteristics, among others, are reflected in the environmental factors considered in determining the allowance for loan losses. The Company assigns all non-consumer loans a credit quality risk rating. These ratings are Pass, Watch, Substandard, Doubtful, and Loss. Loans with a Pass and Watch rating represent those loans not classified on the Company’s rating scale for problem credits, with loans with a Watch rating being monitored and updated at least quarterly by management. Substandard loans are those where a well-defined weakness has been identified that may put full collection of contractual debt at risk. Doubtful loans are those where a well-defined weakness has been identified and a loss of contractual debt is probable. Substandard and doubtful loans are monitored and updated monthly. All loan risk ratings are updated and monitored on a continuous basis. The Company generally does not risk rate consumer loans unless a default event such as bankruptcy or extended nonperformance takes place. Alternatively, standard credit scoring systems are used to assess credit risks of consumer loans. Troubled Debt Restructurings (“TDRs”) Loans modified under troubled debt restructurings involve granting a concession to a borrower who is experiencing financial difficulty. These concessions could include a reduction in the interest rate on the loan, payment extensions, forgiveness of principal, forbearance, or other actions intended to maximize collection, which generally would not otherwise be considered. Our TDRs include performing and nonperforming TDRs, which consist of loans that continue to accrue interest at the loan's original interest rate as we expect to collect the remaining principal and interest on the loan, and nonaccrual TDRs, which include loans that are in a nonaccrual status and are no longer accruing interest, as we do not expect to collect the full amount of principal and interest owned from the borrower on these loans. At the time of modification (except for loans on nonaccrual status), a TDR is classified as nonperforming TDR until a six -month payment history of principal and interest payments, in accordance with the terms of the loan modification, is sustained, at which time we move the loan to a performing status (performing TDR). If we do not expect to collect all principal and interest on the loan, the modified loan is classified as a nonaccrual TDR. All TDRs are accounted for as impaired loans and are included in our analysis of the allowance for loan losses. A TDR that has been renewed for a borrower who is no longer experiencing financial difficulty and which yields a market rate of interest at the time of a renewal is no longer considered a TDR. Allowance for Loan Losses (“ALL”) and Unfunded Commitments The Company maintains an allowance for loan losses at a level management believes is appropriate to reserve for credit losses inherent in our loan portfolio. The allowance for loan losses is determined based on an ongoing evaluation, driven primarily by monitoring changes in loan risk grades, delinquencies, and other credit risk indicators, which is inherently subjective. The Company considers the uncertainty related to certain industry sectors and the extent of credit exposure to specific borrowers within the portfolio. In addition, consideration is given to concentration risks associated with the various loan portfolios and current economic conditions that might impact the portfolio. The Company also considers changes, if any, in underwriting activities, the loan portfolio composition (including product mix and geographic, industry, or customer-specific concentrations), trends in loan performance, the level of allowance coverage relative to similar banking institutions and macroeconomic factors, such as changes in unemployment rates, gross domestic product, and consumer bankruptcy filings. All of these estimates are susceptible to significant change. Changes to the allowance for loan losses are made by charges to the provision for loan losses, which is reflected in the consolidated statements of comprehensive income. Past due status is monitored as an indicator of credit deterioration. Loans that are 90 days or more past due are put on nonaccrual status unless the loan is well secured and in the process of collection. Loans deemed to be uncollectible are charged off against the allowance for loan losses. Recoveries of amounts previously charged-off are credited to the allowance for loan losses. The allowance for loan losses consist of reserves for probable losses that have been identified related to specific borrowing relationships that are individually evaluated for impairment (“specific reserve”), as well as probable losses inherent in our loan portfolio that are not specifically identified (“collective reserve”). The specific reserve relates to impaired loans. A loan is impaired when, based on current information and events, it is probable the Company will be unable to collect all amounts due (interest as well as principal) according to the contractual terms of the loan agreement. Specific reserves are determined on a loan-by-loan basis based on management’s best estimate of the Company’s exposure, given the current payment status of the loan, the present value of expected payments, and the value of any underlying collateral. Impaired loans also include loans modified in troubled debt restructurings. Generally, the impairment related to troubled debt restructurings is measured based on the fair value of the collateral, less cost to sell, or the present value of expected payments relative to the unpaid principal balance. If the impaired loan is identified as collateral dependent, then the fair value of the collateral method of measuring the amount of the impairment is utilized. This method requires obtaining an independent appraisal of the collateral and applying a discount factor to the appraised value, if necessary, and including costs to sell. Management’s estimate for collective reserves reflects losses incurred in the loan portfolio as of the consolidated balance sheet reporting date. Incurred loss estimates primarily are based on historical loss experience and portfolio mix. Incurred loss estimates may be adjusted for qualitative factors such as current economic conditions and current portfolio trends including credit quality, concentrations, aging of the portfolio, and/or significant policy and underwriting changes. The Company maintains an ALL for acquired impaired loans accounted for under ASC 310-30, resulting from decreases in expected cash flows arising from the periodic revaluation of these loans Any decrease in expected cash flows in the individual loan pool is generally recognized in the current provision for loan losses. Any increase in expected cash flows is generally not recognized immediately but is instead reflected as an adjustment to the related loan or pool's yield on a prospective basis once any previously recorded provision for loan loss has been recognized. For acquired nonimpaired loans accounted for under ASC 310-20, the Company utilizes methods to estimate the required allowance for loan losses similar to originated loans; the required reserve is compared to the net carrying value of each acquired nonimpaired loan (by segment) to determine if a provision is required. While management uses the best information available to establish the allowance for loan losses, future adjustments may be necessary if economic conditions differ substantially from the assumptions used in performing the estimates. Unfunded residential mortgage loan commitments entered into in connection with mortgage loans to be held for sale are considered derivatives and are recorded at fair value and included in other liabilities on the consolidated balance sheets with changes in fair value recorded in other interest income. All other unfunded loan commitments are generally related to providing credit facilities to customers and are not considered derivatives. For purchased loans, the fair value of the unfunded credit commitments is considered in determination of the fair value of the loans recorded at the date of acquisition. Reserves for credit exposure on all other unfunded credit commitments are recorded in other liabilities on the consolidated balance sheets.
FDIC Indemnification Asset and Clawback Liability	In conjunction with a Federal Deposit Insurance Corporation (“FDIC”)-assisted transaction of TierOne Bank in 2010, the Company entered into two loss share agreements with the FDIC, one covering certain single family residential mortgage loans with the claim period ending June 2020 and one covering commercial loans and other assets, in which the claim period ended in June 2015. The agreements cover a portion of realized losses on loans, foreclosed real estate and certain other assets. The Company has recorded assets on the consolidated balance sheets (i.e. indemnification assets) representing estimated future amounts recoverable from the FDIC. Fair values of loans covered by the loss sharing agreements at the acquisition date were estimated based on projected cash flows available based on the expected probability of default, default timing and loss given default, the expected reimbursement rates (generally 80% ) from the FDIC and other relevant terms of the loss sharing agreements. The initial fair value was established by discounting these expected cash flows with a market discount rate for instruments with like maturity and risk characteristics. The loss share assets are measured separately from the related loans and foreclosed real estate and recorded as an FDIC indemnification asset on the consolidated balance sheets because they are not contractually embedded in the loans and are not transferable with the loans should the Company choose to dispose of them. Subsequent to the acquisition date, reimbursements received from the FDIC for actual incurred losses reduce the carrying amount of the loss share assets. Reductions to expected losses on covered assets, to the extent such reductions to expected losses are the result of an improvement to the actual or expected cash flows from the covered assets, also reduce the carrying amount of the loss share assets. The rate of accretion of the indemnification asset discount included in interest income slows to mirror the accelerated accretion of the loan discount. Additional expected losses on covered assets, to the extent such expected losses result in the recognition of an allowance for loan losses, increase the carrying amount of the loss share assets. A related increase in the value of the indemnification asset up to the amount covered by the FDIC is calculated based on the reimbursement rates from the FDIC and is included in other noninterest income. The corresponding loan accretion or amortization is recorded as a component of interest income on the consolidated statements of comprehensive income. Although these assets are contractual receivables from the FDIC, there are no contractual interest rates. As part of the loss sharing agreements, the Company also assumed a liability (“FDIC Clawback Liability”) to be paid within 45 days subsequent to the maturity or termination of the loss sharing agreements that is contingent upon actual losses incurred over the life of the agreements relative to expected losses considered in the consideration paid at acquisition date and the amount of losses reimbursed to the Company under the loss sharing agreements. The liability was recorded at fair value as of the acquisition date. The fair value was based on a discounted cash flow calculation that considered the formula defined in the loss sharing agreements and projected losses. The difference between the fair value at acquisition date and the projected losses is amortized through other noninterest expense. As projected losses and reimbursements are updated, as described above, the FDIC Clawback Liability is adjusted and a gain or loss is recorded in other noninterest expense.
Core Deposits and Other Intangibles	Intangible assets consist of core deposits, brand intangible, customer relationships, and other intangibles. Core deposits represent the identifiable intangible value assigned to core deposit bases arising from purchase acquisitions. Brand intangible represents the value associated with the Bank charter. Customer relationships intangible represents the identifiable intangible value assigned to customer relationships arising from a purchase acquisition. Other intangibles represent contractual franchise arrangements under which the franchiser grants the franchisee the right to perform certain functions within a designated geographical area. The methods and lives used to amortize intangible assets are as follows: Intangible Method Years Core deposit Straight-line or effective yield 5 Brand intangible Straight-line 15 Customer relationships Straight-line 8.5 Other intangibles Straight-line 5 Intangible assets are evaluated for impairment whenever events or changes in circumstances indicate that the carrying value may not be recoverable.
Derivatives	The Company maintains an overall interest rate risk management strategy that permits the use of derivative instruments to modify exposure to interest rate risk. The Company enters into interest rate swap contracts to offset the interest rate risk associated with borrowers who lock in long-term fixed rates (greater than or equal to 5 years to maturity) through a fixed rate loan. These contracts do not qualify for hedge accounting. Generally, under these swaps, the Company agrees with various swap counterparties to exchange the difference between fixed-rate and floating-rate interest amounts based upon notional principal amounts. These interest rate derivative instruments are recognized as assets and liabilities on the consolidated balance sheets and measured at fair value, with changes in fair value reported in net realized and unrealized gain (loss) on derivatives. Since each fixed rate loan is paired with an offsetting derivative contract, the impact to net income is minimized. The Company enters into forward interest rate lock commitments on mortgage loans to be held for sale, which are commitments to originate loans whereby the interest rate on the loan is determined prior to funding. The Company also has corresponding forward sales contracts related to these interest rate lock commitments. Both the mortgage loan commitments and the related sales contracts are considered derivatives and are recorded at fair value with changes in fair value recorded in noninterest income.
Stock Based Compensation	Restricted and performance-based stock units/awards are classified as equity awards and accounted for under the Treasury method. Compensation expense for non-vested stock units/awards is based on the fair value of the award on the measurement date, which, for the Company, is the date of the grant and is recognized ratably over the vesting or performance period of the award. The fair value of non-vested stock units/awards is generally the market price of the Company's stock on the date of grant.
Income Taxes	The Company was required to file a consolidated income tax return with National Americas Investment, Inc. ("NAI") (a wholly owned indirect subsidiary of NAB) until NAI's dissolution on October 17, 2014. Income taxes are allocated pursuant to a tax-sharing arrangement, whereby the Company will pay federal and state income taxes as if it were filing on a stand-alone basis. Income tax expense includes two components: current and deferred. Current income tax expense reflects taxes to be paid or refunded for the current period by applying the provisions of the enacted tax law to the taxable income or excess of deductions over income. The Company determines deferred income taxes using the liability (or balance sheet) method. Under this method, the net deferred tax asset or liability is based on the tax effects of the differences between the book and tax basis of assets and liabilities, and enacted changes in tax rates and laws are recognized in the period in which they occur. Deferred income tax expense results from changes in deferred tax assets and liabilities between periods. Deferred tax assets are reduced by a valuation allowance if, based on the weight of evidence available, it is more likely than not that some portion or all of a deferred tax asset will not be realized. Tax benefits related to uncertain tax positions are recognized if it is more likely than not, based on the technical merits, that the tax position will be realized or sustained upon examination. The term "more likely than not" means a likelihood of more than 50 percent; the terms "examined" and "upon examination" also include resolution of the related appeals or litigation processes, if any. A tax position that meets the more-likely-than-not recognition threshold is initially and subsequently measured as the largest amount of tax benefit that has a greater than 50 percent likelihood of being realized upon settlement with a taxing authority that has full knowledge of all relevant information. The determination of whether or not a tax position has met the more-likely-than-not recognition threshold considers the facts, circumstances, and information available at the reporting date and is subject to management’s judgment.
Transfers of Financial Assets	Transfers of financial assets are accounted for as sales when control over the assets has been surrendered. Control over transferred assets is deemed to be surrendered when (1) the assets have been isolated from the Company-put presumptively beyond reach of the Company and its creditors, even in bankruptcy or other receivership, (2) the transferee obtains the right (free of conditions that constrain it from taking advantage of that right) to pledge or exchange the transferred assets, and (3) the Company does not maintain effective control over the transferred assets through an agreement to repurchase them before their maturity or the ability to unilaterally cause the holder to return specific assets. Securities sold under agreements to repurchase are accounted for as collateralized financing transactions and are recorded at amounts at which the securities were financed, plus accrued interest.
Revenue Recognition	The Company recognizes revenue as it is earned based on contractual terms, as transactions occur, or as services are provided and collectability is reasonably assured. Certain specific policies related to service charges and other fees include the following: Deposit Service Charges Service charges on deposit accounts are primarily fees related to customer overdraft events and not sufficient funds fees, net of any refunded fees, and are recognized as transactions occur and services are provided. Service charges on deposit accounts also relate to monthly fees based on minimum balances, and are earned as transactions occur and services are provided. Interchange Fees Interchange fees include interchange income from consumer debit card transactions processed through card association networks. Interchange income is a fee paid by a merchant bank to the card-issuing bank through the interchange network. Interchange fees are set by the card association networks and are based on cardholder purchase volumes. Wealth Management Fees Wealth management fees include commission income from financial planning, investment management and insurance operations.
Comprehensive Income	Comprehensive income consists of net income and other comprehensive income, net of applicable income taxes. Other comprehensive income (loss) consists entirely of unrealized appreciation (depreciation) on available-for-sale securities.
Subsequent Events	The Company has evaluated all events or transactions that occurred through the date the Company issued these financial statements. During this period, the Company did not have any material recognizable or non-recognizable subsequent events other than outlined below.

Nature of Operations and Summ26

Nature of Operations and Summary of Significant Policies (Tables)	6 Months Ended
	Mar. 31, 2016
Accounting Policies [Abstract]
Schedule of Finite-lived Intangible Assets	The methods and lives used to amortize intangible assets are as follows: Intangible Method Years Core deposit Straight-line or effective yield 5 Brand intangible Straight-line 15 Customer relationships Straight-line 8.5 Other intangibles Straight-line 5 A summary of intangible assets subject to amortization is as follows (in thousands): Core Deposit Brand Customer Total As of March 31, 2016 Gross carrying amount $ 92,679 $ 8,464 $ 16,089 $ 117,232 Accumulated amortization (92,260 ) (4,418 ) (14,852 ) (111,530 ) Net intangible assets $ 419 $ 4,046 $ 1,237 $ 5,702 As of September 30, 2015 Gross carrying amount $ 92,679 $ 8,464 $ 16,089 $ 117,232 Accumulated amortization (92,073 ) (4,136 ) (13,904 ) (110,113 ) Net intangible assets $ 606 $ 4,328 $ 2,185 $ 7,119

Securities Available for Sale (

Securities Available for Sale (Tables)	6 Months Ended
	Mar. 31, 2016
Investments, Debt and Equity Securities [Abstract]
Amortized Cost and Fair Value	The amortized cost and approximate fair value of investments in securities, all of which are classified as available for sale according to management’s intent, are summarized as follows (in thousands): Amortized Cost Gross Gross Estimated Fair Value As of March 31, 2016 U.S. Treasury securities $ 226,497 $ 4,340 $ — $ 230,837 U.S. Agency securities 74,480 516 — 74,996 Mortgage-backed securities: Government National Mortgage Association 743,435 4,008 (3,033 ) 744,410 Federal National Mortgage Association 135,323 616 — 135,939 Small Business Assistance Program 133,878 1,123 — 135,001 States and political subdivision securities 1,458 — — 1,458 Corporate debt securities 4,997 — (6 ) 4,991 Other 1,006 47 — 1,053 Total $ 1,321,074 $ 10,650 $ (3,039 ) $ 1,328,685 Amortized Cost Gross Gross Estimated Fair Value As of September 30, 2015 U.S. Treasury securities $ 250,986 $ 3,811 $ — $ 254,797 U.S. Agency securities 74,412 643 — 75,055 Mortgage-backed securities: Government National Mortgage Association 842,460 3,663 (4,503 ) 841,620 Federal National Mortgage Association 46,449 96 — 46,545 Small Business Assistance Program 101,415 233 (213 ) 101,435 States and political subdivision securities 1,849 1 — 1,850 Corporate debt securities 4,996 — (13 ) 4,983 Other 1,006 36 — 1,042 Total $ 1,323,573 $ 8,483 $ (4,729 ) $ 1,327,327
Marketable Securities	The amortized cost and approximate fair value of debt securities available for sale as of March 31, 2016 and September 30, 2015 , by contractual maturity, are shown below. Maturities of mortgage-backed securities may differ from contractual maturities because the mortgages underlying the securities may be called or repaid without any penalties. March 31, 2016 September 30, 2015 (In Thousands) Amortized Cost Estimated Fair Value Amortized Cost Estimated Fair Value Due in one year or less $ 74,825 $ 75,341 $ 76,261 $ 76,905 Due after one year through five years 231,645 235,979 255,982 259,780 Due after five years through ten years 962 962 — — 307,432 312,282 332,243 336,685 Mortgage-backed securities 1,012,636 1,015,350 990,324 989,600 Securities without contractual maturities 1,006 1,053 1,006 1,042 Total $ 1,321,074 $ 1,328,685 $ 1,323,573 $ 1,327,327
Schedule of Unrealized Loss on Investments	The following table presents the Company’s gross unrealized losses and approximate fair value in investments, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position (in thousands): March 31, 2016 Less than 12 months 12 months or more Total Estimated Fair Value Unrealized Losses Estimated Fair Value Unrealized Losses Estimated Fair Value Unrealized Losses U.S. Treasury securities $ — $ — $ — $ — $ — $ — U.S. Agency securities — — — — — — Mortgage-backed securities 24,380 (43 ) 305,508 (2,990 ) 329,888 (3,033 ) Corporate debt securities 4,992 (6 ) — — 4,992 (6 ) Total $ 29,372 $ (49 ) $ 305,508 $ (2,990 ) $ 334,880 $ (3,039 ) September 30, 2015 Less than 12 months 12 months or more Total Estimated Fair Value Unrealized Losses Estimated Fair Value Unrealized Losses Estimated Fair Value Unrealized Losses U.S. Treasury securities $ — $ — $ — $ — $ — $ — U.S. Agency securities — — — — — — Mortgage-backed securities 58,604 (236 ) 412,058 (4,480 ) 470,662 (4,716 ) Corporate debt securities 4,984 (13 ) — — 4,984 (13 ) Total $ 63,588 $ (249 ) $ 412,058 $ (4,480 ) $ 475,646 $ (4,729 )
Unrealized Gain (Loss) on Investments	The components of accumulated other comprehensive income (loss) from net unrealized gains (losses) on securities available for sale for the three and six months ended March 31, 2016 and 2015 , respectively are as follows (in thousands): Three Months Ended Six Months Ended 2016 2015 2016 2015 Beginning balance accumulated other comprehensive income (loss) $ (5,289 ) $ (3,042 ) $ 2,318 $ (6,157 ) Net unrealized holding gain arising during the period 16,102 8,312 4,187 13,285 Reclassification adjustment for net gain (loss) realized in net income 24 — (330 ) (51 ) Net change in unrealized gain before income taxes 16,126 8,312 3,857 13,234 Income tax (expense) (6,128 ) (3,159 ) (1,466 ) (4,966 ) Net change in unrealized gain on securities after taxes 9,998 5,153 2,391 8,268 Ending balance accumulated other comprehensive income $ 4,709 $ 2,111 $ 4,709 $ 2,111

Loans (Tables)

Loans (Tables)	6 Months Ended
	Mar. 31, 2016
Receivables [Abstract]
Schedule of Loans Receivable	The composition of loans as of March 31, 2016 and September 30, 2015 , is as follows (in thousands): March 31, 2016 September 30, 2015 Residential real estate $ 909,590 $ 921,827 Commercial real estate 3,078,028 2,845,748 Commercial non real estate 1,588,356 1,610,828 Agriculture 1,900,013 1,861,465 Consumer 64,465 73,049 Other 39,510 38,371 Ending balance 7,579,962 7,351,288 Less: Unamortized discount on acquired loans (16,829 ) (19,264 ) Unearned net deferred fees and costs and loans in process (5,345 ) (6,826 ) Total $ 7,557,788 $ 7,325,198
Schedule of Company's Nonaccrual Loans	The following table presents the Company’s nonaccrual loans at March 31, 2016 and September 30, 2015 (in thousands), excluding loans acquired with deteriorated credit quality. Loans greater than 90 days past due and still accruing interest as of March 31, 2016 and September 30, 2015 , were not significant. Nonaccrual loans March 31, 2016 September 30, 2015 Residential real estate $ 6,853 $ 7,642 Commercial real estate 9,932 9,556 Commercial non real estate 9,944 14,281 Agriculture 17,377 24,569 Consumer 60 107 Total $ 44,166 $ 56,155
Composition of Loan Portfolio by Internal Risk Rating	This table (in thousands) is presented net of unamortized discount on acquired loans and excludes loans measured at fair value with changes in fair value reported in earnings of $1.17 billion at March 31, 2016 and $1.12 billion at September 30, 2015 : As of March 31, 2016 Residential Commercial Commercial Agriculture Consumer Other Total Credit Risk Profile by Internally Assigned Grade Grade: Pass $ 797,470 $ 2,589,340 $ 1,007,498 $ 1,257,519 $ 63,918 $ 39,510 $ 5,755,255 Watchlist 4,454 98,291 53,285 177,317 250 — 333,597 Substandard 11,731 59,036 32,728 118,390 279 — 222,164 Doubtful 107 186 652 — — — 945 Loss — — — — — — — Ending balance 813,762 2,746,853 1,094,163 1,553,226 64,447 39,510 6,311,961 Loans covered by FDIC loss sharing agreements 85,517 — — — — — 85,517 Total $ 899,279 $ 2,746,853 $ 1,094,163 $ 1,553,226 $ 64,447 $ 39,510 $ 6,397,478 As of September 30, 2015 Residential Commercial Commercial Agriculture Consumer Other Total Credit Risk Profile by Internally Assigned Grade Grade: Pass $ 799,359 $ 2,384,980 $ 1,053,091 $ 1,272,312 $ 72,705 $ 38,371 $ 5,620,818 Watchlist 4,890 66,024 50,242 189,144 78 — 310,378 Substandard 11,877 56,905 60,801 53,837 223 — 183,643 Doubtful 323 200 682 256 7 — 1,468 Loss — — — — — — — Ending balance 816,449 2,508,109 1,164,816 1,515,549 73,013 38,371 6,116,307 Loans covered by FDIC loss sharing agreements 97,030 — — — — — 97,030 Total $ 913,479 $ 2,508,109 $ 1,164,816 $ 1,515,549 $ 73,013 $ 38,371 $ 6,213,337
Past Due Financing Receivables	The following table (in thousands) presents the Company’s past due loans at March 31, 2016 and September 30, 2015 . This table is presented net of unamortized discount on acquired loans and excludes loans measured at fair value with changes in fair value reported in earnings of $1.17 billion at March 31, 2016 and $1.12 billion at September 30, 2015 . As of March 31, 2016 30-59 Days 60-89 Days 90 Days or Greater Past Due Total Current Total Residential real estate $ 1,669 $ 31 $ 2,084 $ 3,784 $ 809,978 $ 813,762 Commercial real estate 1,281 165 6,020 7,466 2,739,387 2,746,853 Commercial non real estate 4,484 266 6,145 10,895 1,083,268 1,094,163 Agriculture 1,292 662 7,276 9,230 1,543,996 1,553,226 Consumer 100 18 8 126 64,321 64,447 Other — — — — 39,510 39,510 Ending balance 8,826 1,142 21,533 31,501 6,280,460 6,311,961 Loans covered by FDIC loss sharing agreements 2,392 295 192 2,879 82,638 85,517 Total $ 11,218 $ 1,437 $ 21,725 $ 34,380 $ 6,363,098 $ 6,397,478 As of September 30, 2015 30-59 Days 60-89 Days 90 Days or Greater Past Due Total Current Total Residential real estate $ 486 $ 858 $ 2,776 $ 4,120 $ 812,329 $ 816,449 Commercial real estate 1,708 1,204 4,247 7,159 2,500,950 2,508,109 Commercial non real estate 697 7,944 4,072 12,713 1,152,103 1,164,816 Agriculture 2,161 175 6,264 8,600 1,506,949 1,515,549 Consumer 232 8 37 277 72,736 73,013 Other — — — — 38,371 38,371 Ending balance 5,284 10,189 17,396 32,869 6,083,438 6,116,307 Loans covered by FDIC loss sharing agreements 2,455 594 873 3,922 93,108 97,030 Total $ 7,739 $ 10,783 $ 18,269 $ 36,791 $ 6,176,546 $ 6,213,337
Impaired Financing Receivables	The following table presents the Company’s impaired loans (in thousands). This table excludes loans covered by FDIC loss sharing agreements: March 31, 2016 September 30, 2015 Recorded Unpaid Related Recorded Unpaid Related Impaired loans: With an allowance recorded: Residential real estate $ 11,942 $ 12,644 $ 3,731 $ 12,364 $ 12,602 $ 2,784 Commercial real estate 86,212 86,984 7,421 67,751 69,722 4,644 Commercial non real estate 34,053 34,311 5,936 65,495 76,647 5,657 Agriculture 118,390 119,514 6,963 54,093 54,699 3,950 Consumer 293 439 56 230 359 50 Total $ 250,890 $ 253,892 $ 24,107 $ 199,933 $ 214,029 $ 17,085 The average recorded investment on impaired loans and interest income recognized on impaired loans for the three and six months ended March 31, 2016 and 2015 , respectively, are as follows: Three Months Ended March 31, 2016 Three Months Ended March 31, 2015 Six Months Ended Six Months Ended Average Interest Income Recognized while on Impaired Status Average Interest Income Recognized while on Impaired Status Average Interest Income Recognized while on Impaired Status Average Interest Income Recognized while on Impaired Status Residential real estate $ 12,124 $ 290 $ 12,379 $ 783 $ 12,204 $ 439 $ 12,288 $ 945 Commercial real estate 83,642 2,004 74,990 4,622 78,345 3,473 70,711 6,392 Commercial non real estate 40,450 766 40,210 2,644 48,798 1,122 37,647 3,445 Agriculture 109,473 3,256 40,056 1,440 91,013 5,695 38,546 1,787 Consumer 308 25 246 42 282 42 257 51 Total $ 245,997 $ 6,341 $ 167,881 $ 9,531 $ 230,642 $ 10,771 $ 159,449 $ 12,620 The following table provides purchased credit impaired loans at March 31, 2016 and September 30, 2015 (in thousands): March 31, 2016 September 30, 2015 Outstanding 1 Recorded 2 Carrying 3 Outstanding 1 Recorded 2 Carrying 3 Residential real estate $ 83,921 $ 72,778 $ 71,260 $ 93,979 $ 82,189 $ 80,565 Commercial real estate 94,831 18,591 17,598 97,302 20,710 19,628 Commercial non real estate 8,957 2,130 2,130 10,387 2,759 2,689 Agriculture 1,481 1,480 1,480 1,538 1,538 1,538 Consumer 1,150 1,050 1,050 1,368 1,271 1,271 Total lending $ 190,340 $ 96,029 $ 93,518 $ 204,574 $ 108,467 $ 105,691 1 Represents the legal balance of loans acquired with deteriorated credit quality. 2 Represents the book balance of loans acquired with deteriorated credit quality. 3 Represents the book balance of loans acquired with deteriorated credit quality net of the related allowance for loan losses.
Troubled Debt Restructurings on Financing Receivables	The following table presents the recorded value of the Company’s TDR balances as of March 31, 2016 and September 30, 2015 (in thousands): March 31, 2016 September 30, 2015 Accruing Nonaccrual Accruing Nonaccrual Residential real estate $ 377 $ 1,142 $ 452 $ 1,547 Commercial real estate 39,391 2,441 30,917 4,725 Commercial non real estate 7,641 1,686 8,928 833 Agriculture 46,527 6,205 20,041 6,857 Consumer 19 18 33 4 Total $ 93,955 $ 11,492 $ 60,371 $ 13,966 The following table presents a summary of all accruing loans restructured in TDRs during the three months ended March 31, 2016 and 2015 , respectively: Three Months Ended March 31, 2016 2015 Recorded Investment Recorded Investment ($ in thousands) Number Pre- Post- Number Pre- Post- Residential real estate Rate modification — $ — $ — 1 $ 15 $ 15 Term extension — — — — — — Payment modification — — — — — — Bankruptcy — — — — — — Other — — — 1 21 21 Total residential real estate — — — 2 36 36 Commercial real estate Rate modification — — — — — — Term extension — — — 1 90 — Payment modification — — — 4 3,660 3,660 Bankruptcy — — — 1 498 498 Other 3 6,714 6,714 — — — Total commercial real estate 3 6,714 6,714 6 4,248 4,158 Commercial non real estate Rate modification 1 49 49 — — — Term extension — — — 3 2,879 2,879 Payment modification 1 70 70 1 50 50 Bankruptcy — — — — — — Other 3 3,849 3,849 — — — Total commercial non real estate 5 3,968 3,968 4 2,929 2,929 Agriculture Rate modification — — — — — — Term extension 5 4,941 4,941 — — — Payment modification 4 989 989 — — — Bankruptcy — — — — — — Other — — — — — — Total agriculture 9 5,930 5,930 — — — Consumer Rate modification — — — — — — Term extension — — — — — — Payment modification — — — — — — Bankruptcy — — — 1 6 6 Other — — — — — — Total consumer — — — 1 6 6 Total accruing 17 $ 16,612 $ 16,612 13 $ 7,219 $ 7,129 Change in recorded investment due to principal paydown at time of modification — $ — $ — — $ — $ — Change in recorded investment due to chargeoffs at time of modification — $ — $ — 1 $ 90 $ — The following table presents a summary of all accruing loans restructured in TDRs during the six months ended March 31, 2016 and 2015 , respectively: Six Months Ended March 31, 2016 2015 Recorded Investment Recorded Investment ($ in thousands) Number Pre- Post- Number Pre- Post- Residential real estate Rate modification — $ — $ — 1 $ 15 $ 15 Term extension — — — — — — Payment modification — — — — — — Bankruptcy — — — — — — Other — — — 1 21 21 Total residential real estate — — — 2 36 36 Commercial real estate Rate modification — — — — — — Term extension 2 1,898 1,898 1 90 — Payment modification — — — 6 22,542 22,542 Bankruptcy — — — 1 498 498 Other 3 6,714 6,714 — — — Total commercial real estate 5 8,612 8,612 8 23,130 23,040 Commercial non real estate Rate modification 1 49 49 1 32 32 Term extension 1 58 58 3 2,879 2,879 Payment modification 1 70 70 2 1,874 1,874 Bankruptcy — — — — — — Other 3 3,849 3,849 — — — Total commercial non real estate 6 4,026 4,026 6 4,785 4,785 Agriculture Rate modification — — — — — — Term extension 13 26,914 26,914 — — — Payment modification 4 989 989 — — — Bankruptcy — — — — — — Other — — — — — — Total agriculture 17 27,903 27,903 — — — Consumer Rate modification — — — — — — Term extension — — — — — — Payment modification — — — — — — Bankruptcy — — — 1 6 6 Other — — — — — — Total consumer — — — 1 6 6 Total accruing 28 $ 40,541 $ 40,541 17 $ 27,957 $ 27,867 Change in recorded investment due to principal paydown at time of modification — $ — $ — — $ — $ — Change in recorded investment due to chargeoffs at time of modification — $ — $ — 1 $ 90 $ — The following table presents a summary of all non-accruing loans restructured in TDRs during the three months ended March 31, 2016 and 2015 : Three Months Ended March 31, 2016 2015 Recorded Investment Recorded Investment ($ in thousands) Number Pre- Post- Number Pre- Post- Residential real estate Rate modification — $ — $ — 2 $ 104 $ 104 Term extension — — — 1 77 77 Payment modification — — — — — — Bankruptcy — — — 1 43 43 Other — — — — — — Total residential real estate — — — 4 224 224 Commercial real estate Rate modification — — — — — — Term extension — — — — — — Payment modification — — — — — — Bankruptcy — — — — — — Other — — — — — — Total commercial real estate — — — — — — Commercial Non Real Estate Rate modification — — — — — — Term extension — — — 4 217 217 Payment modification 1 364 364 — — — Bankruptcy — — — — — — Other — — — — — — Total commercial non real estate 1 364 364 4 217 217 Agriculture Rate modification — — — — — — Term extension — — — — — — Payment modification — — — — — — Bankruptcy — — — — — — Other — — — — — — Total agriculture — — — — — — Consumer Rate modification — — — — — — Term extension — — — 1 1 1 Payment modification — — — — — — Bankruptcy 1 8 8 — — — Other — — — — — — Total consumer 1 8 8 1 1 1 Total non-accruing 2 $ 372 $ 372 9 $ 442 $ 442 Change in recorded investment due to principal paydown at time of modification — $ — $ — — $ — $ — Change in recorded investment due to chargeoffs at time of modification — $ — $ — — $ — $ — The following table presents a summary of all non-accruing loans restructured in TDRs during the six months ended March 31, 2016 and 2015 : Six Months Ended March 31, 2016 2015 Recorded Investment Recorded Investment ($ in thousands) Number Pre- Post- Number Pre- Post- Residential real estate Rate modification — $ — $ — 2 $ 104 $ 104 Term extension — — — 1 77 77 Payment modification 1 187 187 — — — Bankruptcy — — — 1 43 43 Other — — — — — — Total residential real estate 1 187 187 4 224 224 Commercial real estate Rate modification — — — — — — Term extension — — — — — — Payment modification — — — — — — Bankruptcy — — — — — — Other — — — — — — Total commercial real estate — — — — — — Commercial Non Real Estate Rate modification — — — — — — Term extension — — — 4 217 217 Payment modification 2 760 760 — — — Bankruptcy — — — — — — Other — — — — — — Total commercial non real estate 2 760 760 4 217 217 Agriculture Rate modification — — — — — — Term extension — — — — — — Payment modification — — — — — — Bankruptcy — — — — — — Other — — — — — — Total agriculture — — — — — — Consumer Rate modification — — — — — — Term extension — — — 1 1 1 Payment modification — — — — — — Bankruptcy 1 8 8 — — — Other — — — — — — Total consumer 1 8 8 1 1 1 Total non-accruing 4 $ 955 $ 955 9 $ 442 $ 442 Change in recorded investment due to principal paydown at time of modification — $ — $ — — $ — $ — Change in recorded investment due to chargeoffs at time of modification — $ — $ — — $ — $ — The tables below represent defaults on loans that were first modified during the respective past 12 months, that became 90 days or more delinquent or were charged-off during the three and six months ended March 31, 2016 and 2015 , respectively. Three Months Ended Six Months Ended 2016 2015 2016 2015 ($ in thousands) Number of Recorded Number of Recorded Number of Recorded Number of Recorded Residential real estate 1 $ — 4 $ 107 1 $ — 10 $ 629 Commercial real estate — — — — — — — — Commercial non real estate — — — — 1 364 1 95 Agriculture 2 — — — 2 — 1 15 Consumer — — — — 1 8 — — Total 3 $ — 4 $ 107 5 $ 372 12 $ 739

Allowance for Loan Losses (Tabl

Allowance for Loan Losses (Tables)	6 Months Ended
	Mar. 31, 2016
Receivables [Abstract]
Allowance for credit losses on financing receivables	The following tables presents the Company’s allowance for loan losses roll forward for the three and six months ended March 31, 2016 and 2015 . Three Months Ended March 31, 2016 Residential Commercial Commercial Agriculture Consumer Other Total Beginning balance January 1, 2016 $ 7,798 $ 19,405 $ 17,160 $ 15,473 $ 341 $ 951 $ 61,128 Charge-offs (506 ) (744 ) (212 ) (1,113 ) (98 ) (597 ) (3,270 ) Recoveries 295 409 235 77 45 367 1,428 Provision 1,218 1,893 (4,552 ) 3,886 48 206 2,699 (Improvement) impairment of (9 ) (59 ) — — — — (68 ) Ending balance March 31, 2016 $ 8,796 $ 20,904 $ 12,631 $ 18,323 $ 336 $ 927 $ 61,917 Three Months Ended March 31, 2015 Residential Commercial Commercial Agriculture Consumer Other Total Beginning balance January 1, 2015 $ 7,567 $ 17,722 $ 14,625 $ 10,920 $ 201 $ 785 $ 51,820 Charge-offs (63 ) (1,570 ) (8,440 ) (27 ) (19 ) (403 ) (10,522 ) Recoveries 70 26 983 22 23 325 1,449 Provision 160 (389 ) 8,789 1,307 (17 ) 120 9,970 (Improvement) impairment of (239 ) (53 ) — — 1 — (291 ) Ending balance March 31, 2015 $ 7,495 $ 15,736 $ 15,957 $ 12,222 $ 189 $ 827 $ 52,426 Six Months Ended March 31, 2016 Residential Commercial Commercial Agriculture Consumer Other Total Beginning balance October 1, $ 8,025 $ 18,014 $ 15,996 $ 13,952 $ 348 $ 865 $ 57,200 Charge-offs (702 ) (772 ) (257 ) (1,124 ) (146 ) (997 ) (3,998 ) Recoveries 339 491 639 124 70 532 2,195 Provision 1,240 3,260 (3,677 ) 5,371 64 527 6,785 (Impairment) improvement of (106 ) (89 ) (70 ) — — — (265 ) Ending balance March 31, 2016 $ 8,796 $ 20,904 $ 12,631 $ 18,323 $ 336 $ 927 $ 61,917 Six Months Ended March 31, 2015 Residential Commercial Commercial Agriculture Consumer Other Total Beginning balance October 1, $ 8,342 $ 16,884 $ 10,550 $ 10,655 $ 264 $ 823 $ 47,518 Charge-offs (120 ) (1,652 ) (8,524 ) (27 ) (57 ) (831 ) (11,211 ) Recoveries 113 95 2,143 79 47 644 3,121 Provision (190 ) 346 11,788 1,515 (41 ) 191 13,609 (Impairment) improvement of (650 ) 63 — — (24 ) — (611 ) Ending balance March 31, 2015 $ 7,495 $ 15,736 $ 15,957 $ 12,222 $ 189 $ 827 $ 52,426 The following tables provide details regarding the allowance for loan and lease losses and balance by type of allowance. These tables (in thousands) are presented net of unamortized discount on acquired loans and excludes loans of $1.17 billion measured at fair value (and the associated credit mark embedded within the carrying value of these loans) with changes in fair value reported in earnings, loans held for sale of $5.9 million , and guaranteed loans of $129.8 million for March 31, 2016 and loans measured at fair value with changes in fair value reported in earnings of $1.12 billion , loans held for sale of $9.9 million , and guaranteed loans of $105.0 million for September 30, 2015 . As of March 31, 2016 Residential Commercial Commercial Agriculture Consumer Other Total Allowance for loan losses Individually evaluated for impairment $ 3,731 $ 7,293 $ 5,932 $ 6,963 $ 56 $ — $ 23,975 Collectively evaluated for impairment 3,547 12,618 6,699 11,360 280 927 35,431 Loans acquired with deteriorated credit quality 1,518 993 — — — — 2,511 Total allowance $ 8,796 $ 20,904 $ 12,631 $ 18,323 $ 336 $ 927 $ 61,917 Financing Receivables Individually evaluated for impairment $ 12,487 $ 50,495 $ 33,374 $ 92,657 $ 261 $ — $ 189,274 Collectively evaluated for impairment 806,809 2,600,323 1,016,396 1,450,270 63,136 39,510 5,976,444 Loans acquired with deteriorated credit quality 72,778 18,591 2,130 1,480 1,050 — 96,029 Loans Outstanding $ 892,074 $ 2,669,409 $ 1,051,900 $ 1,544,407 $ 64,447 $ 39,510 $ 6,261,747 As of September 30, 2015 Residential Commercial Commercial Agriculture Consumer Other Total Allowance for loan losses Individually evaluated for impairment $ 2,783 $ 4,585 $ 5,624 $ 3,950 $ 50 $ — $ 16,992 Collectively evaluated for impairment 3,618 12,347 10,302 10,002 298 865 37,432 Loans acquired with deteriorated credit quality 1,624 1,082 70 — — — 2,776 Total allowance $ 8,025 $ 18,014 $ 15,996 $ 13,952 $ 348 $ 865 $ 57,200 Financing Receivables Individually evaluated for impairment $ 13,106 $ 49,794 $ 62,158 $ 44,253 $ 193 $ — $ 169,504 Collectively evaluated for impairment 806,912 2,385,636 1,056,806 1,461,230 71,549 38,371 5,820,504 Loans acquired with deteriorated credit quality 82,189 20,710 2,759 1,538 1,271 — 108,467 Loans Outstanding $ 902,207 $ 2,456,140 $ 1,121,723 $ 1,507,021 $ 73,013 $ 38,371 $ 6,098,475

Accounting for Certain Loans 30

Accounting for Certain Loans Acquired with Deteriorated Credit Quality (Tables)	6 Months Ended
	Mar. 31, 2016
Receivables [Abstract]
Troubled Debt Restructurings on Financing Receivables	The re-assessment of purchased credit impaired loans resulted in the following changes in the accretable yield during the three and six months ended March 31, 2016 and 2015 (in thousands): Three Months Ended Six Months Ended 2016 2015 2016 2015 Balance at beginning of period $ 41,882 $ 46,342 $ 44,489 $ 50,889 Accretion (2,261 ) (3,222 ) (4,590 ) (8,009 ) Reclassification from (to) nonaccretable difference 222 311 (56 ) 631 Disposals — — — (80 ) Balance at end of period $ 39,843 $ 43,431 $ 39,843 $ 43,431
Impaired Financing Receivables	The following table presents the Company’s impaired loans (in thousands). This table excludes loans covered by FDIC loss sharing agreements: March 31, 2016 September 30, 2015 Recorded Unpaid Related Recorded Unpaid Related Impaired loans: With an allowance recorded: Residential real estate $ 11,942 $ 12,644 $ 3,731 $ 12,364 $ 12,602 $ 2,784 Commercial real estate 86,212 86,984 7,421 67,751 69,722 4,644 Commercial non real estate 34,053 34,311 5,936 65,495 76,647 5,657 Agriculture 118,390 119,514 6,963 54,093 54,699 3,950 Consumer 293 439 56 230 359 50 Total $ 250,890 $ 253,892 $ 24,107 $ 199,933 $ 214,029 $ 17,085 The average recorded investment on impaired loans and interest income recognized on impaired loans for the three and six months ended March 31, 2016 and 2015 , respectively, are as follows: Three Months Ended March 31, 2016 Three Months Ended March 31, 2015 Six Months Ended Six Months Ended Average Interest Income Recognized while on Impaired Status Average Interest Income Recognized while on Impaired Status Average Interest Income Recognized while on Impaired Status Average Interest Income Recognized while on Impaired Status Residential real estate $ 12,124 $ 290 $ 12,379 $ 783 $ 12,204 $ 439 $ 12,288 $ 945 Commercial real estate 83,642 2,004 74,990 4,622 78,345 3,473 70,711 6,392 Commercial non real estate 40,450 766 40,210 2,644 48,798 1,122 37,647 3,445 Agriculture 109,473 3,256 40,056 1,440 91,013 5,695 38,546 1,787 Consumer 308 25 246 42 282 42 257 51 Total $ 245,997 $ 6,341 $ 167,881 $ 9,531 $ 230,642 $ 10,771 $ 159,449 $ 12,620 The following table provides purchased credit impaired loans at March 31, 2016 and September 30, 2015 (in thousands): March 31, 2016 September 30, 2015 Outstanding 1 Recorded 2 Carrying 3 Outstanding 1 Recorded 2 Carrying 3 Residential real estate $ 83,921 $ 72,778 $ 71,260 $ 93,979 $ 82,189 $ 80,565 Commercial real estate 94,831 18,591 17,598 97,302 20,710 19,628 Commercial non real estate 8,957 2,130 2,130 10,387 2,759 2,689 Agriculture 1,481 1,480 1,480 1,538 1,538 1,538 Consumer 1,150 1,050 1,050 1,368 1,271 1,271 Total lending $ 190,340 $ 96,029 $ 93,518 $ 204,574 $ 108,467 $ 105,691 1 Represents the legal balance of loans acquired with deteriorated credit quality. 2 Represents the book balance of loans acquired with deteriorated credit quality. 3 Represents the book balance of loans acquired with deteriorated credit quality net of the related allowance for loan losses.

FDIC Indemnification Asset (Tab

FDIC Indemnification Asset (Tables)	6 Months Ended
	Mar. 31, 2016
Banking and Thrift [Abstract]
FDIC indemnification asset roll forward	The following table represents a summary of the activity related to the FDIC indemnification asset for the three and six months ended March 31, 2016 and 2015 (in thousands): Three Months Ended Six Months Ended 2016 2015 2016 2015 Balance at beginning of period $ 13,185 $ 22,162 $ 14,722 $ 26,678 Amortization (895 ) (2,060 ) (1,927 ) (4,593 ) Changes in expected reimbursements from FDIC for changes in expected credit losses 1 2 (127 ) (190 ) Changes in reimbursable expenses (78 ) (207 ) (427 ) (363 ) Payments (reimbursements) of covered losses from the FDIC 662 (2 ) 634 (1,637 ) Balance at end of period $ 12,875 $ 19,895 $ 12,875 $ 19,895

Derivative Financial Instrume32

Derivative Financial Instruments (Tables)	6 Months Ended
	Mar. 31, 2016
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Derivative Positions, Notional Amounts	The following table summarizes the notional amounts and estimated fair values of the Company’s derivative instruments at March 31, 2016 and September 30, 2015 (in thousands). March 31, 2016 Notional Balance Sheet Positive Fair Negative Fair Derivatives not designated as hedging instruments: Interest rate swaps $ 1,094,357 Liabilities $ 10 $ (74,155 ) Mortgage loan commitments 32,556 Assets 52 — Mortgage loan forward sale contracts 34,757 Liabilities — (52 ) September 30, 2015 Notional Balance Sheet Positive Fair Negative Fair Derivatives not designated as hedging instruments: Interest rate swaps $ 1,087,505 Liabilities $ 41 $ (53,559 ) Mortgage loan commitments 30,196 Assets 95 — Mortgage loan forward sale contracts 36,655 Liabilities — (95 )
Schedule of Derivative Instruments, Effect on Other Comprehensive Income	The effect of derivatives on the consolidated statements of comprehensive income for the three and six months ended March 31, 2016 and 2015 (in thousands) was as follows: Amount of Gain (Loss) Recognized in Income Three Months Ended Six Months Ended Location of 2016 2015 2016 2015 Derivatives not designated as hedging instruments: Interest rate swaps Noninterest income $ (40,893 ) $ (21,698 ) $ (31,454 ) $ (46,303 ) Mortgage loan commitments Noninterest income 76 13 52 27 Mortgage loan forward sale contracts Noninterest income (76 ) (13 ) (52 ) (27 )
Summary of Offsetting Assets	The following tables (in thousands) present the Company's total gross derivative assets and liabilities at March 31, 2016 and September 30, 2015 , which are adjusted on an aggregate basis, where applicable, to take into consideration the effects of legally enforceable master netting agreements for the net reported amount in the consolidated balance sheets. These amounts are offset on the consolidated balance sheets. Gross Amount Net Amount Held/Pledged 1 Net March 31, 2016 Derivative financial assets: Derivatives subject to master netting arrangement or similar arrangement $ 10 $ (10 ) $ — $ — $ — Derivative financial liabilities: Derivatives subject to master netting arrangement or similar arrangement (74,155 ) 10 (74,145 ) 74,145 — Total derivative financial liabilities $ (74,145 ) $ — $ (74,145 ) $ 74,145 $ — 1 The actual amount of collateral exceeds the fair value exposure, at the individual counterparty level, as of the date presented. Gross Amount Net Amount Held/Pledged Net September 30, 2015 Derivative financial assets: Derivatives subject to master netting arrangement or similar arrangement $ 41 $ (41 ) $ — $ — $ — Derivative financial liabilities: Derivatives subject to master netting arrangement or similar arrangement (53,559 ) 41 (53,518 ) 53,518 — Total derivative financial liabilities $ (53,518 ) $ — $ (53,518 ) $ 53,518 $ —
Summary of Offsetting Liabilities	The following tables (in thousands) present the Company's total gross derivative assets and liabilities at March 31, 2016 and September 30, 2015 , which are adjusted on an aggregate basis, where applicable, to take into consideration the effects of legally enforceable master netting agreements for the net reported amount in the consolidated balance sheets. These amounts are offset on the consolidated balance sheets. Gross Amount Net Amount Held/Pledged 1 Net March 31, 2016 Derivative financial assets: Derivatives subject to master netting arrangement or similar arrangement $ 10 $ (10 ) $ — $ — $ — Derivative financial liabilities: Derivatives subject to master netting arrangement or similar arrangement (74,155 ) 10 (74,145 ) 74,145 — Total derivative financial liabilities $ (74,145 ) $ — $ (74,145 ) $ 74,145 $ — 1 The actual amount of collateral exceeds the fair value exposure, at the individual counterparty level, as of the date presented. Gross Amount Net Amount Held/Pledged Net September 30, 2015 Derivative financial assets: Derivatives subject to master netting arrangement or similar arrangement $ 41 $ (41 ) $ — $ — $ — Derivative financial liabilities: Derivatives subject to master netting arrangement or similar arrangement (53,559 ) 41 (53,518 ) 53,518 — Total derivative financial liabilities $ (53,518 ) $ — $ (53,518 ) $ 53,518 $ —

The Fair Value Option For Cer33

The Fair Value Option For Certain Loans (Tables)	6 Months Ended
	Mar. 31, 2016
Fair Value Disclosures [Abstract]
Summary of Fair Value Option	Changes in fair value for items for which the fair value option has been elected and the line items in which these changes are reported within the consolidated statements of comprehensive income are as follows for the three and six months ended March 31, 2016 and 2015 (in thousands): For the Three Months Ended For the Six Months Ended March 31, 2016 March 31, 2015 March 31, 2016 March 31, 2015 Noninterest Total Changes Noninterest Total Changes Noninterest Total Changes Noninterest Total Changes Long-term loans and written loan commitments $ 35,956 $ 35,956 $ 15,208 $ 15,208 $ 21,055 $ 21,055 $ 32,308 $ 32,308

Core Deposits and Other Intan34

Core Deposits and Other Intangibles (Tables)	6 Months Ended
	Mar. 31, 2016
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Finite-lived Intangible Assets	The methods and lives used to amortize intangible assets are as follows: Intangible Method Years Core deposit Straight-line or effective yield 5 Brand intangible Straight-line 15 Customer relationships Straight-line 8.5 Other intangibles Straight-line 5 A summary of intangible assets subject to amortization is as follows (in thousands): Core Deposit Brand Customer Total As of March 31, 2016 Gross carrying amount $ 92,679 $ 8,464 $ 16,089 $ 117,232 Accumulated amortization (92,260 ) (4,418 ) (14,852 ) (111,530 ) Net intangible assets $ 419 $ 4,046 $ 1,237 $ 5,702 As of September 30, 2015 Gross carrying amount $ 92,679 $ 8,464 $ 16,089 $ 117,232 Accumulated amortization (92,073 ) (4,136 ) (13,904 ) (110,113 ) Net intangible assets $ 606 $ 4,328 $ 2,185 $ 7,119
Schedule of Finite-lived Intangible Assets, Future Amortization Expense	Estimated amortization expense of intangible assets in subsequent fiscal years is as follows (in thousands): Remaining in 2016 $ 1,405 2017 1,097 2018 564 2019 564 2020 564 2021 and thereafter 1,508 Total $ 5,702

Securities Sold Under Agreeme35

Securities Sold Under Agreements to Repurchase (Tables)	6 Months Ended
	Mar. 31, 2016
Federal Funds Purchased and Securities Sold under Agreements to Repurchase [Abstract]
Schedule of Repurchase Agreements	The following tables present the gross obligation by the class of collateral pledged and the remaining contractual maturity of the agreements at March 31, 2016 and September 30, 2015 (in thousands). March 31, 2016 Remaining Contractual Maturity of the Agreements Overnight and Continuous Up to 30 Days 30-90 Days Greater than 90 Days Total Repurchase agreements US Treasury and agency $ — $ — $ — $ — $ — Mortgage-backed securities 143,329 — — 2,944 146,273 Total repurchase agreements $ 143,329 $ — $ — $ 2,944 $ 146,273 September 30, 2015 Remaining Contractual Maturity of the Agreements Overnight and Continuous Up to 30 Days 30-90 Days Greater than 90 Days Total Repurchase agreements US Treasury and agency $ 64,252 $ — $ — $ — $ 64,252 Mortgage-backed securities 118,147 — — 2,872 121,019 Total repurchase agreements $ 182,399 $ — $ — $ 2,872 $ 185,271

FHLB Advances and Other Borro36

FHLB Advances and Other Borrowings (Tables)	6 Months Ended
	Mar. 31, 2016
Federal Home Loan Banks [Abstract]
Schedule of FHLB Advances and Other Borrowings	FHLB advances and other borrowings consist of the following at March 31, 2016 and September 30, 2015 (in thousands): March 31, 2016 September 30, 2015 Notes payable to Federal Home Loan Bank (FHLB), interest rates from 0.43% to 3.66% and maturity dates from April 2016 to July 2023, collateralized by real estate loans and FHLB stock, with various call dates at the option of the FHLB $ 370,000 $ 581,000
Schedule of FHLB Advances and Other Borrowings by Maturity Date	As of March 31, 2016 , FHLB advances and other borrowings are due or callable (whichever is earlier) in subsequent fiscal years as follows (in thousands): Remaining in 2016 $ 60,000 2017 25,000 2018 25,000 2019 — 2020 — 2021 and thereafter 260,000 Total $ 370,000

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	6 Months Ended
	Mar. 31, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Schedule of Share-Based Compensation, Restricted Stock Units Award Activity	The following is a summary of the Plans’ restricted share and performance-based stock award activity as of March 31, 2016 and September 30, 2015 : March 31, 2016 September 30, 2015 Restricted Shares Common Shares Weighted-Average Common Shares Weighted-Average Restricted shares, beginning of fiscal year 80,446 $ 18.18 — $ — Granted 91,896 30.73 81,419 18.18 Vested and issued (25,526 ) 18.06 — — Forfeited (1,181 ) 24.69 (973 ) 18.00 Canceled — — — — Restricted shares, end of period 145,635 $ 26.07 80,446 $ 18.18 Vested, but not issuable at end of period 24,480 $ 26.14 12,221 $ 18.00 Performance Shares Performance shares, beginning of fiscal year 211,026 $ 18.00 — $ — Granted 43,371 30.78 221,294 18.00 Vested and issued (55 ) 18.00 — — Forfeited (4,236 ) 19.22 (10,268 ) 18.00 Canceled — — — — Performance shares, end of period 250,106 $ 20.20 211,026 $ 18.00

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	6 Months Ended
	Mar. 31, 2016
Fair Value Disclosures [Abstract]
Schedule of Fair Value Measurements, Assets and Liabilities	The following table presents the fair value measurements of assets and liabilities recognized in the accompanying consolidated balance sheets measured at fair value on a recurring basis and the level within the fair value hierarchy in which the fair value measurements fall at March 31, 2016 and September 30, 2015 (in thousands): Fair Value Level 1 Level 2 Level 3 As of March 31, 2016 U.S. Treasury securities $ 230,837 $ 230,837 $ — $ — U.S. Agency securities 74,996 74,996 — — Mortgage-backed securities 1,015,350 — 1,015,350 — States and political subdivision securities 1,458 — — 1,458 Corporate debt securities 4,991 — 4,991 — Other 1,053 — 1,053 — Securities available for sale $ 1,328,685 $ 305,833 $ 1,021,394 $ 1,458 Derivatives-assets $ 52 $ 52 $ — Derivatives-liabilities 74,197 — 74,197 — Fair value loans and written loan commitments 1,165,660 — 1,165,660 — Fair Value Level 1 Level 2 Level 3 As of September 30, 2015 U.S. Treasury securities $ 254,797 $ 254,797 $ — $ — U.S. Agency securities 75,055 75,055 — — Mortgage-backed securities 989,600 — 989,600 — States and political subdivision securities 1,850 — 15 1,835 Corporate debt securities 4,983 — 4,983 — Other 1,042 — 1,042 — Securities available for sale $ 1,327,327 $ 329,852 $ 995,640 $ 1,835 Derivatives-assets $ 95 $ — $ 95 $ — Derivatives-liabilities 53,613 — 53,613 — Fair value loans and written loan commitments 1,118,687 — 1,118,687 —
Schedule of Available-for-Sale Securities Reconciliation	The following table presents the changes in Level 3 financial instruments for the three and six months ended March 31, 2016 and 2015 (in thousands): Other Securities Available for Sale Three months ended March 31, Six months ended March 31, 2016 2015 2016 2015 Balance, beginning of period $ 1,458 $ 1,958 $ 1,835 $ 2,029 Principal paydown — — (77 ) (71 ) Realized loss on securities — — (300 ) — Balance, end of period $ 1,458 $ 1,958 $ 1,458 $ 1,958
Mortgage Loans Held-for-Sale, Fair Value Measurement	The following tables present the fair value measurement of assets and liabilities measured at fair value on a nonrecurring basis and the level within the fair value hierarchy in which the fair value measurements fall at March 31, 2016 and September 30, 2015 (in thousands): Fair Value Level 1 Level 2 Level 3 As of March 31, 2016 Other real estate owned $ 1,068 $ — $ — $ 1,068 Impaired loans 165,924 — — 165,924 Loans held for sale, at lower of cost or fair value 5,918 — 5,918 — As of September 30, 2015 Other real estate owned $ 8,826 $ — $ — $ 8,826 Impaired loans 153,318 — — 153,318 Loans held for sale, at lower of cost or fair value 9,867 — 9,867 —
Mortgage Loans Held-for-Sale, Recurring and Nonrecurring Fair Value Measurements	The valuation techniques and significant unobservable inputs used to measure Level 3 fair value measurements at March 31, 2016 were as follows (in thousands): Financial Fair Value of Assets / (Liabilities) at March 31, 2016 Valuation Unobservable Range Weighted Other real estate owned $ 1,068 Appraisal value Property specific adjustment N/A N/A Impaired loans $ 165,924 Appraisal value Property specific adjustment N/A N/A
Fair Value, by Balance Sheet Grouping	Fair values for balance sheet instruments as of March 31, 2016 and September 30, 2015 , are as follows (in thousands): March 31, 2016 September 30, 2015 Level in Carrying Fair Value Carrying Fair Value Assets Cash and due from banks Level 1 $ 174,401 $ 174,401 $ 237,770 $ 237,770 Loans, net excluding fair valued loans and loans Level 3 6,324,293 6,300,553 6,139,444 6,120,262 Accrued interest receivable Level 2 39,487 39,487 44,077 44,077 Federal Home Loan Bank stock Level 2 27,127 27,127 35,745 35,745 Liabilities Deposits Level 2 $ 7,712,729 $ 7,711,376 $ 7,387,065 $ 7,385,894 FHLB advances and other borrowings Level 2 370,000 373,559 581,000 584,261 Securities sold under repurchase agreements Level 2 146,273 146,273 185,271 185,271 Accrued interest payable Level 2 3,987 3,987 4,006 4,006 Subordinated debentures and subordinated notes payable Level 2 90,764 91,764 90,727 91,305

Earnings per Share (Tables)

Earnings per Share (Tables)	6 Months Ended
	Mar. 31, 2016
Earnings Per Share [Abstract]
Schedule of Basic and Diluted Earnings per Share	The following information was used in the computation of basic earnings per share (EPS) for the three and six months ended March 31, 2016 and 2015 (in thousands except share data). Three Months Ended Six Months Ended 2016 2015 2016 2015 Net income $ 30,674 $ 19,724 $ 61,135 $ 46,421 Weighted average common shares outstanding 55,269,557 57,898,335 55,261,634 57,897,059 Dilutive effect of stock based compensation 139,319 18,467 139,530 9,234 Weighted average common shares outstanding for diluted earnings per share calculation 55,408,876 57,916,802 55,401,164 57,906,293 Basic earnings per share $ 0.56 $ 0.34 $ 1.11 $ 0.80 Diluted earnings per share $ 0.55 $ 0.34 $ 1.10 $ 0.80

Nature of Operations and Summ40

Nature of Operations and Summary of Significant Policies (Details)	May. 13, 2016USD ($)$ / sharesshares	Apr. 28, 2016$ / shares	Mar. 31, 2016$ / shares	Mar. 31, 2015$ / shares	Mar. 31, 2016USD ($)portfolio_class$ / shares	Mar. 31, 2015USD ($)$ / shares	Dec. 31, 2010agreement
Accounts, Notes, Loans and Financing Receivable [Line Items]
Maturity period of loans and loan commitments					5 years
Period for loans held for sale to be carried at cost and sold					45 days
Number of portfolio classes | portfolio_class					6
Nonperforming classification, payment history period					6 months
FDIC Indemnification, number of loss share agreements entered | agreement							2
FDIC Indemnification, expected reimbursement rate					80.00%
FDIC Clawback Liability, payment period following termination or maturity of agreement					45 days
Impairment of intangible assets | $					$ 0	$ 0
Subsequent Event [Line Items]
Common stock dividends declared (in dollars per share) | $ / shares			$ 0.1399323682	$ 0.1199861792	$ 0.2798867656	$ 0.1199888236
Subsequent event
Subsequent Event [Line Items]
Common stock dividends declared (in dollars per share) | $ / shares		$ 0.14
Core deposit
Accounts, Notes, Loans and Financing Receivable [Line Items]
Intangible asset, useful life					5 years
Brand intangible
Accounts, Notes, Loans and Financing Receivable [Line Items]
Intangible asset, useful life					15 years
Customer relationships
Accounts, Notes, Loans and Financing Receivable [Line Items]
Intangible asset, useful life					8 years 6 months
Other intangibles
Accounts, Notes, Loans and Financing Receivable [Line Items]
Intangible asset, useful life					5 years
Minimum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Maturity period of loans and loan commitments					5 years
Maximum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Maturity period of loans and loan commitments					15 years
Residential loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
FDIC Indemnification, number of loss share agreements entered | agreement							1
Commercial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
FDIC Indemnification, number of loss share agreements entered | agreement							1
HF Financial Corporation | Forecast
Subsequent Event [Line Items]
Equity interest issued per share as part of merger (shares) | shares	0.6500
Consideration paid as part of merger (in dollars per share) | $ / shares	$ 19.50
Percentage of outstanding shares exchanged for cash as part of merger	25.00%
Percentage of outstanding shares exchanged for common stock as part of merger	75.00%
Cash consideration | $	$ 34,500,000
Number of shares issued as part of business combination | shares	3,450,000

Securities Available for Sale -

Securities Available for Sale - (Narrative) (Details)	3 Months Ended		6 Months Ended
	Mar. 31, 2016USD ($)security	Mar. 31, 2015USD ($)	Mar. 31, 2016USD ($)security	Mar. 31, 2015USD ($)	Sep. 30, 2015USD ($)security
Investments, Debt and Equity Securities [Abstract]
Proceeds from sales of securities available for sale	$ 25,000,000	$ 0	$ 24,996,000	$ 55,149,000
Available-for-sale securities, gross realized gains	0	0	0	600,000
Available-for-sale securities, gross realized losses	0	0	0	500,000
Other than temporary impairment losses recognized in earnings	$ 0	$ 0	$ 400,000	$ 0
Number of securities written off | security	2		2
Securities pledged as collateral	$ 888,900,000		$ 888,900,000		$ 894,300,000
Percentage of investment portfolio in continuous loss position	25.00%		25.00%		36.00%
Number of securities in an unrealized loss position (securities) | security	25		25		31
Federal home loan bank stock	$ 27,100,000		$ 27,100,000		$ 35,700,000

Securities Available for Sale

Securities Available for Sale - Amortized Cost and Fair Value (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Sep. 30, 2015
Available-for-sale Securities, Fair Value to Amortized Cost Basis [Abstract]
Amortized Cost	$ 1,321,074	$ 1,323,573
Gross Unrealized Gains	10,650	8,483
Gross Unrealized Losses	(3,039)	(4,729)
Estimated Fair Value	1,328,685	1,327,327
U.S. Treasury securities
Available-for-sale Securities, Fair Value to Amortized Cost Basis [Abstract]
Amortized Cost	226,497	250,986
Gross Unrealized Gains	4,340	3,811
Gross Unrealized Losses	0	0
Estimated Fair Value	230,837	254,797
U.S. Agency securities
Available-for-sale Securities, Fair Value to Amortized Cost Basis [Abstract]
Amortized Cost	74,480	74,412
Gross Unrealized Gains	516	643
Gross Unrealized Losses	0	0
Estimated Fair Value	74,996	75,055
States and political subdivision securities
Available-for-sale Securities, Fair Value to Amortized Cost Basis [Abstract]
Amortized Cost	1,458	1,849
Gross Unrealized Gains	0	1
Gross Unrealized Losses	0	0
Estimated Fair Value	1,458	1,850
Corporate debt securities
Available-for-sale Securities, Fair Value to Amortized Cost Basis [Abstract]
Amortized Cost	4,997	4,996
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(6)	(13)
Estimated Fair Value	4,991	4,983
Other
Available-for-sale Securities, Fair Value to Amortized Cost Basis [Abstract]
Amortized Cost	1,006	1,006
Gross Unrealized Gains	47	36
Gross Unrealized Losses	0	0
Estimated Fair Value	1,053	1,042
Government National Mortgage Association | Mortgage backed-securities, Issued by US Government
Available-for-sale Securities, Fair Value to Amortized Cost Basis [Abstract]
Amortized Cost	743,435	842,460
Gross Unrealized Gains	4,008	3,663
Gross Unrealized Losses	(3,033)	(4,503)
Estimated Fair Value	744,410	841,620
Federal National Mortgage Association | Mortgage backed-securities, Issued by US Government
Available-for-sale Securities, Fair Value to Amortized Cost Basis [Abstract]
Amortized Cost	135,323	46,449
Gross Unrealized Gains	616	96
Gross Unrealized Losses	0	0
Estimated Fair Value	135,939	46,545
Small Business Assistance Program | Mortgage backed-securities, Issued by US Government
Available-for-sale Securities, Fair Value to Amortized Cost Basis [Abstract]
Amortized Cost	133,878	101,415
Gross Unrealized Gains	1,123	233
Gross Unrealized Losses	0	(213)
Estimated Fair Value	$ 135,001	$ 101,435

Securities Available for Sale43

Securities Available for Sale - Schedule of Available For Sale Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Sep. 30, 2015
Amortized Cost
Due in one year or less	$ 74,825	$ 76,261
Due after one year through five years	231,645	255,982
Due after five years through ten years	962	0
Amortized Cost	307,432	332,243
Estimated Fair Value
Due in one year or less	75,341	76,905
Due after one year through five years	235,979	259,780
Due after five years through ten years	962	0
Fair Value	312,282	336,685
Amortized Cost	1,321,074	1,323,573
Estimated Fair Value	1,328,685	1,327,327
Securities without contractual maturities, Amortized Cost	1,006	1,006
Securities without contractual maturities, Fair Value	1,053	1,042
Mortgage-backed securities
Estimated Fair Value
Amortized Cost	1,012,636	990,324
Estimated Fair Value	$ 1,015,350	$ 989,600

Securities Available for Sale44

Securities Available for Sale - Schedule of Gross Unrealized Losses (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Sep. 30, 2015
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value [Abstract]
Less than 12 months, Estimated Fair Value	$ 29,372	$ 63,588
12 months or more, Estimated Fair Value	305,508	412,058
Fair Value	334,880	475,646
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss [Abstract]
Less than 12 months, Unrealized Losses	(49)	(249)
12 months or more, Unrealized Losses	(2,990)	(4,480)
Unrealized Losses	(3,039)	(4,729)
U.S. Treasury securities
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value [Abstract]
Less than 12 months, Estimated Fair Value	0	0
12 months or more, Estimated Fair Value	0	0
Fair Value	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss [Abstract]
Less than 12 months, Unrealized Losses	0	0
12 months or more, Unrealized Losses	0	0
Unrealized Losses	0	0
U.S. Agency securities
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value [Abstract]
Less than 12 months, Estimated Fair Value	0	0
12 months or more, Estimated Fair Value	0	0
Fair Value	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss [Abstract]
Less than 12 months, Unrealized Losses	0	0
12 months or more, Unrealized Losses	0	0
Unrealized Losses	0	0
Mortgage-backed securities
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value [Abstract]
Less than 12 months, Estimated Fair Value	24,380	58,604
12 months or more, Estimated Fair Value	305,508	412,058
Fair Value	329,888	470,662
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss [Abstract]
Less than 12 months, Unrealized Losses	(43)	(236)
12 months or more, Unrealized Losses	(2,990)	(4,480)
Unrealized Losses	(3,033)	(4,716)
Corporate debt securities
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value [Abstract]
Less than 12 months, Estimated Fair Value	4,992	4,984
12 months or more, Estimated Fair Value	0	0
Fair Value	4,992	4,984
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss [Abstract]
Less than 12 months, Unrealized Losses	(6)	(13)
12 months or more, Unrealized Losses	0	0
Unrealized Losses	$ (6)	$ (13)

Securities Available for Sale45

Securities Available for Sale - Unrealized Gain (Loss) On Investments (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2016	Mar. 31, 2015
Accumulated Other Comprehensive Income (Loss), before Tax [Roll Forward]
Beginning balance accumulated other comprehensive income (loss)	$ (5,289)	$ (3,042)	$ 2,318	$ (6,157)
Net unrealized holding gain arising during the period	16,102	8,312	4,187	13,285
Reclassification adjustment for net gain (loss) realized in net income	24	0	(330)	(51)
Net change in unrealized gain before income taxes	16,126	8,312	3,857	13,234
Income tax (expense)	(6,128)	(3,159)	(1,466)	(4,966)
Net change in unrealized gain on securities after taxes	9,998	5,153	2,391	8,268
Ending balance accumulated other comprehensive income	$ 4,709	$ 2,111	$ 4,709	$ 2,111

Loans - Narrative (Details)

Loans - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2016	Mar. 31, 2015	Sep. 30, 2015
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans covered by FDIC loss share agreements	$ 85,517		$ 85,517		$ 97,030
Loans held for sale	5,918		5,918		9,867
Loans and written loan commitments at fair value under the fair value option	1,165,660		1,165,660		1,118,687
Unamortized discount on acquired loans	7,200		7,200		7,500
Loans in process	(1,900)		(1,900)		(700)
Loans guaranteed by U.S. Government Agencies	6,261,747		6,261,747		6,098,475
Principal balances of residential real estate loans sold	50,400	$ 69,600	108,600	$ 133,900
Valuation adjustments made to repossessed properties	500	$ 2,200	500	$ 4,300
Specific reserves included in the allowance for loan losses for TDRs	7,900		7,900		3,600
Troubled debt restructuring, commitments to lend additional funds	1,700		1,700		2,300
Loans Guaranteed by US Government Authorities
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans guaranteed by U.S. Government Agencies	$ 129,800		$ 129,800		$ 105,000

Loans - Schedule of Financing R

Loans - Schedule of Financing Receivable (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Sep. 30, 2015
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total financing receivables, gross	$ 7,579,962	$ 7,351,288
Unamortized discount on acquired loans	(16,829)	(19,264)
Unearned net deferred fees and costs and loans in process	(5,345)	(6,826)
Net loans	7,557,788	7,325,198
Residential real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total financing receivables, gross	909,590	921,827
Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total financing receivables, gross	3,078,028	2,845,748
Commercial non real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total financing receivables, gross	1,588,356	1,610,828
Agriculture
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total financing receivables, gross	1,900,013	1,861,465
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total financing receivables, gross	64,465	73,049
Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total financing receivables, gross	$ 39,510	$ 38,371

Loans - Composition of the Loan

Loans - Composition of the Loan Portfolio by Internal Risk Rating (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Sep. 30, 2015
Financing Receivable, Recorded Investment [Line Items]
Nonaccrual loans, excluding loans covered under FDIC loss-sharing arrangements	$ 44,166	$ 56,155
Total financing receivables	6,311,961	6,116,307
Loans covered by FDIC loss share agreements	85,517	97,030
Total	6,397,478	6,213,337
Pass
Financing Receivable, Recorded Investment [Line Items]
Total financing receivables	5,755,255	5,620,818
Watchlist
Financing Receivable, Recorded Investment [Line Items]
Total financing receivables	333,597	310,378
Substandard
Financing Receivable, Recorded Investment [Line Items]
Total financing receivables	222,164	183,643
Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total financing receivables	945	1,468
Loss
Financing Receivable, Recorded Investment [Line Items]
Total financing receivables	0	0
Residential real estate
Financing Receivable, Recorded Investment [Line Items]
Nonaccrual loans, excluding loans covered under FDIC loss-sharing arrangements	6,853	7,642
Total financing receivables	813,762	816,449
Loans covered by FDIC loss share agreements	85,517	97,030
Total	899,279	913,479
Residential real estate | Pass
Financing Receivable, Recorded Investment [Line Items]
Total financing receivables	797,470	799,359
Residential real estate | Watchlist
Financing Receivable, Recorded Investment [Line Items]
Total financing receivables	4,454	4,890
Residential real estate | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total financing receivables	11,731	11,877
Residential real estate | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total financing receivables	107	323
Residential real estate | Loss
Financing Receivable, Recorded Investment [Line Items]
Total financing receivables	0	0
Commercial real estate
Financing Receivable, Recorded Investment [Line Items]
Nonaccrual loans, excluding loans covered under FDIC loss-sharing arrangements	9,932	9,556
Total financing receivables	2,746,853	2,508,109
Loans covered by FDIC loss share agreements	0	0
Total	2,746,853	2,508,109
Commercial real estate | Pass
Financing Receivable, Recorded Investment [Line Items]
Total financing receivables	2,589,340	2,384,980
Commercial real estate | Watchlist
Financing Receivable, Recorded Investment [Line Items]
Total financing receivables	98,291	66,024
Commercial real estate | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total financing receivables	59,036	56,905
Commercial real estate | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total financing receivables	186	200
Commercial real estate | Loss
Financing Receivable, Recorded Investment [Line Items]
Total financing receivables	0	0
Commercial non real estate
Financing Receivable, Recorded Investment [Line Items]
Nonaccrual loans, excluding loans covered under FDIC loss-sharing arrangements	9,944	14,281
Total financing receivables	1,094,163	1,164,816
Loans covered by FDIC loss share agreements	0	0
Total	1,094,163	1,164,816
Commercial non real estate | Pass
Financing Receivable, Recorded Investment [Line Items]
Total financing receivables	1,007,498	1,053,091
Commercial non real estate | Watchlist
Financing Receivable, Recorded Investment [Line Items]
Total financing receivables	53,285	50,242
Commercial non real estate | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total financing receivables	32,728	60,801
Commercial non real estate | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total financing receivables	652	682
Commercial non real estate | Loss
Financing Receivable, Recorded Investment [Line Items]
Total financing receivables	0	0
Agriculture
Financing Receivable, Recorded Investment [Line Items]
Nonaccrual loans, excluding loans covered under FDIC loss-sharing arrangements	17,377	24,569
Total financing receivables	1,553,226	1,515,549
Loans covered by FDIC loss share agreements	0	0
Total	1,553,226	1,515,549
Agriculture | Pass
Financing Receivable, Recorded Investment [Line Items]
Total financing receivables	1,257,519	1,272,312
Agriculture | Watchlist
Financing Receivable, Recorded Investment [Line Items]
Total financing receivables	177,317	189,144
Agriculture | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total financing receivables	118,390	53,837
Agriculture | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total financing receivables	0	256
Agriculture | Loss
Financing Receivable, Recorded Investment [Line Items]
Total financing receivables	0	0
Consumer
Financing Receivable, Recorded Investment [Line Items]
Nonaccrual loans, excluding loans covered under FDIC loss-sharing arrangements	60	107
Total financing receivables	64,447	73,013
Loans covered by FDIC loss share agreements	0	0
Total	64,447	73,013
Consumer | Pass
Financing Receivable, Recorded Investment [Line Items]
Total financing receivables	63,918	72,705
Consumer | Watchlist
Financing Receivable, Recorded Investment [Line Items]
Total financing receivables	250	78
Consumer | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total financing receivables	279	223
Consumer | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total financing receivables	0	7
Consumer | Loss
Financing Receivable, Recorded Investment [Line Items]
Total financing receivables	0	0
Other
Financing Receivable, Recorded Investment [Line Items]
Total financing receivables	39,510	38,371
Loans covered by FDIC loss share agreements	0	0
Total	39,510	38,371
Other | Pass
Financing Receivable, Recorded Investment [Line Items]
Total financing receivables	39,510	38,371
Other | Watchlist
Financing Receivable, Recorded Investment [Line Items]
Total financing receivables	0	0
Other | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total financing receivables	0	0
Other | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total financing receivables	0	0
Other | Loss
Financing Receivable, Recorded Investment [Line Items]
Total financing receivables	$ 0	$ 0

Loans - Past Due Loans (Details

Loans - Past Due Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Sep. 30, 2015
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables, net of unamortized discount on acquired loans	$ 6,311,961	$ 6,116,307
Loans covered by FDIC loss sharing agreements	85,517	97,030
Total	6,397,478	6,213,337
Residential real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables, net of unamortized discount on acquired loans	813,762	816,449
Loans covered by FDIC loss sharing agreements	85,517	97,030
Total	899,279	913,479
Commercial real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables, net of unamortized discount on acquired loans	2,746,853	2,508,109
Loans covered by FDIC loss sharing agreements	0	0
Total	2,746,853	2,508,109
Commercial non real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables, net of unamortized discount on acquired loans	1,094,163	1,164,816
Loans covered by FDIC loss sharing agreements	0	0
Total	1,094,163	1,164,816
Agriculture
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables, net of unamortized discount on acquired loans	1,553,226	1,515,549
Loans covered by FDIC loss sharing agreements	0	0
Total	1,553,226	1,515,549
Consumer
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables, net of unamortized discount on acquired loans	64,447	73,013
Loans covered by FDIC loss sharing agreements	0	0
Total	64,447	73,013
Other
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables, net of unamortized discount on acquired loans	39,510	38,371
Loans covered by FDIC loss sharing agreements	0	0
Total	39,510	38,371
Current
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables, net of unamortized discount on acquired loans	6,280,460	6,083,438
Loans covered by FDIC loss sharing agreements	82,638	93,108
Total	6,363,098	6,176,546
Current | Residential real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables, net of unamortized discount on acquired loans	809,978	812,329
Current | Commercial real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables, net of unamortized discount on acquired loans	2,739,387	2,500,950
Current | Commercial non real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables, net of unamortized discount on acquired loans	1,083,268	1,152,103
Current | Agriculture
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables, net of unamortized discount on acquired loans	1,543,996	1,506,949
Current | Consumer
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables, net of unamortized discount on acquired loans	64,321	72,736
Current | Other
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables, net of unamortized discount on acquired loans	39,510	38,371
Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables, net of unamortized discount on acquired loans	31,501	32,869
Loans covered by FDIC loss sharing agreements	2,879	3,922
Total	34,380	36,791
Past Due | Residential real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables, net of unamortized discount on acquired loans	3,784	4,120
Past Due | Commercial real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables, net of unamortized discount on acquired loans	7,466	7,159
Past Due | Commercial non real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables, net of unamortized discount on acquired loans	10,895	12,713
Past Due | Agriculture
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables, net of unamortized discount on acquired loans	9,230	8,600
Past Due | Consumer
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables, net of unamortized discount on acquired loans	126	277
Past Due | Other
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables, net of unamortized discount on acquired loans	0	0
Past Due | 30-59 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables, net of unamortized discount on acquired loans	8,826	5,284
Loans covered by FDIC loss sharing agreements	2,392	2,455
Total	11,218	7,739
Past Due | 30-59 Days Past Due | Residential real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables, net of unamortized discount on acquired loans	1,669	486
Past Due | 30-59 Days Past Due | Commercial real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables, net of unamortized discount on acquired loans	1,281	1,708
Past Due | 30-59 Days Past Due | Commercial non real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables, net of unamortized discount on acquired loans	4,484	697
Past Due | 30-59 Days Past Due | Agriculture
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables, net of unamortized discount on acquired loans	1,292	2,161
Past Due | 30-59 Days Past Due | Consumer
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables, net of unamortized discount on acquired loans	100	232
Past Due | 30-59 Days Past Due | Other
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables, net of unamortized discount on acquired loans	0	0
Past Due | 60-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables, net of unamortized discount on acquired loans	1,142	10,189
Loans covered by FDIC loss sharing agreements	295	594
Total	1,437	10,783
Past Due | 60-89 Days Past Due | Residential real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables, net of unamortized discount on acquired loans	31	858
Past Due | 60-89 Days Past Due | Commercial real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables, net of unamortized discount on acquired loans	165	1,204
Past Due | 60-89 Days Past Due | Commercial non real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables, net of unamortized discount on acquired loans	266	7,944
Past Due | 60-89 Days Past Due | Agriculture
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables, net of unamortized discount on acquired loans	662	175
Past Due | 60-89 Days Past Due | Consumer
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables, net of unamortized discount on acquired loans	18	8
Past Due | 60-89 Days Past Due | Other
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables, net of unamortized discount on acquired loans	0	0
Past Due | 90 Days or Greater Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables, net of unamortized discount on acquired loans	21,533	17,396
Loans covered by FDIC loss sharing agreements	192	873
Total	21,725	18,269
Past Due | 90 Days or Greater Past Due | Residential real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables, net of unamortized discount on acquired loans	2,084	2,776
Past Due | 90 Days or Greater Past Due | Commercial real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables, net of unamortized discount on acquired loans	6,020	4,247
Past Due | 90 Days or Greater Past Due | Commercial non real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables, net of unamortized discount on acquired loans	6,145	4,072
Past Due | 90 Days or Greater Past Due | Agriculture
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables, net of unamortized discount on acquired loans	7,276	6,264
Past Due | 90 Days or Greater Past Due | Consumer
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables, net of unamortized discount on acquired loans	8	37
Past Due | 90 Days or Greater Past Due | Other
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables, net of unamortized discount on acquired loans	$ 0	$ 0

Loans - Impaired Financing Rece

Loans - Impaired Financing Receivables (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2016	Mar. 31, 2015	Sep. 30, 2015
Financing Receivable, Impaired [Line Items]
Recorded Investment	$ 250,890		$ 250,890		$ 199,933
Unpaid Principal Balance	253,892		253,892		214,029
Related Allowance	24,107		24,107		17,085
Average Recorded Investment	245,997	$ 167,881	230,642	$ 159,449
Interest Income Recognized while on Impaired Status	6,341	9,531	10,771	12,620
Residential real estate
Financing Receivable, Impaired [Line Items]
Recorded Investment	11,942		11,942		12,364
Unpaid Principal Balance	12,644		12,644		12,602
Related Allowance	3,731		3,731		2,784
Average Recorded Investment	12,124	12,379	12,204	12,288
Interest Income Recognized while on Impaired Status	290	783	439	945
Commercial real estate
Financing Receivable, Impaired [Line Items]
Recorded Investment	86,212		86,212		67,751
Unpaid Principal Balance	86,984		86,984		69,722
Related Allowance	7,421		7,421		4,644
Average Recorded Investment	83,642	74,990	78,345	70,711
Interest Income Recognized while on Impaired Status	2,004	4,622	3,473	6,392
Commercial non real estate
Financing Receivable, Impaired [Line Items]
Recorded Investment	34,053		34,053		65,495
Unpaid Principal Balance	34,311		34,311		76,647
Related Allowance	5,936		5,936		5,657
Average Recorded Investment	40,450	40,210	48,798	37,647
Interest Income Recognized while on Impaired Status	766	2,644	1,122	3,445
Agriculture
Financing Receivable, Impaired [Line Items]
Recorded Investment	118,390		118,390		54,093
Unpaid Principal Balance	119,514		119,514		54,699
Related Allowance	6,963		6,963		3,950
Average Recorded Investment	109,473	40,056	91,013	38,546
Interest Income Recognized while on Impaired Status	3,256	1,440	5,695	1,787
Consumer
Financing Receivable, Impaired [Line Items]
Recorded Investment	293		293		230
Unpaid Principal Balance	439		439		359
Related Allowance	56		56		$ 50
Average Recorded Investment	308	246	282	257
Interest Income Recognized while on Impaired Status	$ 25	$ 42	$ 42	$ 51

Loans - Troubled Debt Restructu

Loans - Troubled Debt Restructurings on Accruing and Nonaccrual Financing Receivables (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2016USD ($)contract	Mar. 31, 2015USD ($)contract	Mar. 31, 2016USD ($)contract	Mar. 31, 2015USD ($)contract	Sep. 30, 2015USD ($)
Accruing
Financing Receivable, Modifications [Line Items]
Recorded value of TDR balance	$ 93,955		$ 93,955		$ 60,371
Financing receivable, modifications, number of contracts | contract	17	13	28	17
Financing receivable, modifications, pre-modification recorded investment	$ 16,612	$ 7,219	$ 40,541	$ 27,957
Financing receivable, modifications, post-modification recorded investment	$ 16,612	$ 7,129	$ 40,541	$ 27,867
Change in recorded investment due to principal paydown at time of modification, number of contracts | contract	0	0	0	0
Change in recorded investment due to principal paydown at time of modification, pre-modification	$ 0	$ 0	$ 0	$ 0
Change in recorded investment due to principal paydown at time of modification, post-modification	$ 0	$ 0	$ 0	$ 0
Change in recorded investment due to chargeoffs at time of modification, number of contracts | contract	0	1	0	1
Change in recorded investment due to chargeoffs at time of modification, pre-modification	$ 0	$ 90	$ 0	$ 90
Change in recorded investment due to chargeoffs at time of modification, post-modification	0	$ 0	0	$ 0
Accruing | Residential real estate
Financing Receivable, Modifications [Line Items]
Recorded value of TDR balance	$ 377		$ 377		452
Financing receivable, modifications, number of contracts | contract	0	2	0	2
Financing receivable, modifications, pre-modification recorded investment	$ 0	$ 36	$ 0	$ 36
Financing receivable, modifications, post-modification recorded investment	0	$ 36	0	$ 36
Accruing | Commercial real estate
Financing Receivable, Modifications [Line Items]
Recorded value of TDR balance	$ 39,391		$ 39,391		30,917
Financing receivable, modifications, number of contracts | contract	3	6	5	8
Financing receivable, modifications, pre-modification recorded investment	$ 6,714	$ 4,248	$ 8,612	$ 23,130
Financing receivable, modifications, post-modification recorded investment	6,714	$ 4,158	8,612	$ 23,040
Accruing | Commercial non real estate
Financing Receivable, Modifications [Line Items]
Recorded value of TDR balance	$ 7,641		$ 7,641		8,928
Financing receivable, modifications, number of contracts | contract	5	4	6	6
Financing receivable, modifications, pre-modification recorded investment	$ 3,968	$ 2,929	$ 4,026	$ 4,785
Financing receivable, modifications, post-modification recorded investment	3,968	$ 2,929	4,026	$ 4,785
Accruing | Agriculture
Financing Receivable, Modifications [Line Items]
Recorded value of TDR balance	$ 46,527		$ 46,527		20,041
Financing receivable, modifications, number of contracts | contract	9	0	17	0
Financing receivable, modifications, pre-modification recorded investment	$ 5,930	$ 0	$ 27,903	$ 0
Financing receivable, modifications, post-modification recorded investment	5,930	$ 0	27,903	$ 0
Accruing | Consumer
Financing Receivable, Modifications [Line Items]
Recorded value of TDR balance	$ 19		$ 19		33
Financing receivable, modifications, number of contracts | contract	0	1	0	1
Financing receivable, modifications, pre-modification recorded investment	$ 0	$ 6	$ 0	$ 6
Financing receivable, modifications, post-modification recorded investment	$ 0	$ 6	$ 0	$ 6
Accruing | Rate modification | Residential real estate
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	0	1	0	1
Financing receivable, modifications, pre-modification recorded investment	$ 0	$ 15	$ 0	$ 15
Financing receivable, modifications, post-modification recorded investment	$ 0	$ 15	$ 0	$ 15
Accruing | Rate modification | Commercial real estate
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	0	0	0	0
Financing receivable, modifications, pre-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Financing receivable, modifications, post-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Accruing | Rate modification | Commercial non real estate
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	1	0	1	1
Financing receivable, modifications, pre-modification recorded investment	$ 49	$ 0	$ 49	$ 32
Financing receivable, modifications, post-modification recorded investment	$ 49	$ 0	$ 49	$ 32
Accruing | Rate modification | Agriculture
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	0	0	0	0
Financing receivable, modifications, pre-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Financing receivable, modifications, post-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Accruing | Rate modification | Consumer
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	0	0	0	0
Financing receivable, modifications, pre-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Financing receivable, modifications, post-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Accruing | Term extension | Residential real estate
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	0	0	0	0
Financing receivable, modifications, pre-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Financing receivable, modifications, post-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Accruing | Term extension | Commercial real estate
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	0	1	2	1
Financing receivable, modifications, pre-modification recorded investment	$ 0	$ 90	$ 1,898	$ 90
Financing receivable, modifications, post-modification recorded investment	$ 0	$ 0	$ 1,898	$ 0
Accruing | Term extension | Commercial non real estate
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	0	3	1	3
Financing receivable, modifications, pre-modification recorded investment	$ 0	$ 2,879	$ 58	$ 2,879
Financing receivable, modifications, post-modification recorded investment	$ 0	$ 2,879	$ 58	$ 2,879
Accruing | Term extension | Agriculture
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	5	0	13	0
Financing receivable, modifications, pre-modification recorded investment	$ 4,941	$ 0	$ 26,914	$ 0
Financing receivable, modifications, post-modification recorded investment	$ 4,941	$ 0	$ 26,914	$ 0
Accruing | Term extension | Consumer
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	0	0	0	0
Financing receivable, modifications, pre-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Financing receivable, modifications, post-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Accruing | Payment modification | Residential real estate
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	0	0	0	0
Financing receivable, modifications, pre-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Financing receivable, modifications, post-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Accruing | Payment modification | Commercial real estate
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	0	4	0	6
Financing receivable, modifications, pre-modification recorded investment	$ 0	$ 3,660	$ 0	$ 22,542
Financing receivable, modifications, post-modification recorded investment	$ 0	$ 3,660	$ 0	$ 22,542
Accruing | Payment modification | Commercial non real estate
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	1	1	1	2
Financing receivable, modifications, pre-modification recorded investment	$ 70	$ 50	$ 70	$ 1,874
Financing receivable, modifications, post-modification recorded investment	$ 70	$ 50	$ 70	$ 1,874
Accruing | Payment modification | Agriculture
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	4	0	4	0
Financing receivable, modifications, pre-modification recorded investment	$ 989	$ 0	$ 989	$ 0
Financing receivable, modifications, post-modification recorded investment	$ 989	$ 0	$ 989	$ 0
Accruing | Payment modification | Consumer
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	0	0	0	0
Financing receivable, modifications, pre-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Financing receivable, modifications, post-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Accruing | Bankruptcy | Residential real estate
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	0	0	0	0
Financing receivable, modifications, pre-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Financing receivable, modifications, post-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Accruing | Bankruptcy | Commercial real estate
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	0	1	0	1
Financing receivable, modifications, pre-modification recorded investment	$ 0	$ 498	$ 0	$ 498
Financing receivable, modifications, post-modification recorded investment	$ 0	$ 498	$ 0	$ 498
Accruing | Bankruptcy | Commercial non real estate
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	0	0	0	0
Financing receivable, modifications, pre-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Financing receivable, modifications, post-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Accruing | Bankruptcy | Agriculture
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	0	0	0	0
Financing receivable, modifications, pre-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Financing receivable, modifications, post-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Accruing | Bankruptcy | Consumer
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	0	1	0	1
Financing receivable, modifications, pre-modification recorded investment	$ 0	$ 6	$ 0	$ 6
Financing receivable, modifications, post-modification recorded investment	$ 0	$ 6	$ 0	$ 6
Accruing | Other | Residential real estate
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	0	1	0	1
Financing receivable, modifications, pre-modification recorded investment	$ 0	$ 21	$ 0	$ 21
Financing receivable, modifications, post-modification recorded investment	$ 0	$ 21	$ 0	$ 21
Accruing | Other | Commercial real estate
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	3	0	3	0
Financing receivable, modifications, pre-modification recorded investment	$ 6,714	$ 0	$ 6,714	$ 0
Financing receivable, modifications, post-modification recorded investment	$ 6,714	$ 0	$ 6,714	$ 0
Accruing | Other | Commercial non real estate
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	3	0	3	0
Financing receivable, modifications, pre-modification recorded investment	$ 3,849	$ 0	$ 3,849	$ 0
Financing receivable, modifications, post-modification recorded investment	$ 3,849	$ 0	$ 3,849	$ 0
Accruing | Other | Agriculture
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	0	0	0	0
Financing receivable, modifications, pre-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Financing receivable, modifications, post-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Accruing | Other | Consumer
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	0	0	0	0
Financing receivable, modifications, pre-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Financing receivable, modifications, post-modification recorded investment	0	$ 0	0	$ 0
Nonaccrual
Financing Receivable, Modifications [Line Items]
Recorded value of TDR balance	$ 11,492		$ 11,492		13,966
Financing receivable, modifications, number of contracts | contract	2	9	4	9
Financing receivable, modifications, pre-modification recorded investment	$ 372	$ 442	$ 955	$ 442
Financing receivable, modifications, post-modification recorded investment	$ 372	$ 442	$ 955	$ 442
Change in recorded investment due to principal paydown at time of modification, number of contracts | contract	0	0	0	0
Change in recorded investment due to principal paydown at time of modification, pre-modification	$ 0	$ 0	$ 0	$ 0
Change in recorded investment due to principal paydown at time of modification, post-modification	$ 0	$ 0	$ 0	$ 0
Change in recorded investment due to chargeoffs at time of modification, number of contracts | contract	0	0	0	0
Change in recorded investment due to chargeoffs at time of modification, pre-modification	$ 0	$ 0	$ 0	$ 0
Change in recorded investment due to chargeoffs at time of modification, post-modification	0	$ 0	0	$ 0
Nonaccrual | Residential real estate
Financing Receivable, Modifications [Line Items]
Recorded value of TDR balance	$ 1,142		$ 1,142		1,547
Financing receivable, modifications, number of contracts | contract	0	4	1	4
Financing receivable, modifications, pre-modification recorded investment	$ 0	$ 224	$ 187	$ 224
Financing receivable, modifications, post-modification recorded investment	0	$ 224	187	$ 224
Nonaccrual | Commercial real estate
Financing Receivable, Modifications [Line Items]
Recorded value of TDR balance	$ 2,441		$ 2,441		4,725
Financing receivable, modifications, number of contracts | contract	0	0	0	0
Financing receivable, modifications, pre-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Financing receivable, modifications, post-modification recorded investment	0	$ 0	0	$ 0
Nonaccrual | Commercial non real estate
Financing Receivable, Modifications [Line Items]
Recorded value of TDR balance	$ 1,686		$ 1,686		833
Financing receivable, modifications, number of contracts | contract	1	4	2	4
Financing receivable, modifications, pre-modification recorded investment	$ 364	$ 217	$ 760	$ 217
Financing receivable, modifications, post-modification recorded investment	364	$ 217	760	$ 217
Nonaccrual | Agriculture
Financing Receivable, Modifications [Line Items]
Recorded value of TDR balance	$ 6,205		$ 6,205		6,857
Financing receivable, modifications, number of contracts | contract	0	0	0	0
Financing receivable, modifications, pre-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Financing receivable, modifications, post-modification recorded investment	0	$ 0	0	$ 0
Nonaccrual | Consumer
Financing Receivable, Modifications [Line Items]
Recorded value of TDR balance	$ 18		$ 18		$ 4
Financing receivable, modifications, number of contracts | contract	1	1	1	1
Financing receivable, modifications, pre-modification recorded investment	$ 8	$ 1	$ 8	$ 1
Financing receivable, modifications, post-modification recorded investment	$ 8	$ 1	$ 8	$ 1
Nonaccrual | Rate modification | Residential real estate
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	0	2	0	2
Financing receivable, modifications, pre-modification recorded investment	$ 0	$ 104	$ 0	$ 104
Financing receivable, modifications, post-modification recorded investment	$ 0	$ 104	$ 0	$ 104
Nonaccrual | Rate modification | Commercial real estate
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	0	0	0	0
Financing receivable, modifications, pre-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Financing receivable, modifications, post-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Nonaccrual | Rate modification | Commercial non real estate
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	0	0	0	0
Financing receivable, modifications, pre-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Financing receivable, modifications, post-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Nonaccrual | Rate modification | Agriculture
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	0	0	0	0
Financing receivable, modifications, pre-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Financing receivable, modifications, post-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Nonaccrual | Rate modification | Consumer
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	0	0	0	0
Financing receivable, modifications, pre-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Financing receivable, modifications, post-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Nonaccrual | Term extension | Residential real estate
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	0	1	0	1
Financing receivable, modifications, pre-modification recorded investment	$ 0	$ 77	$ 0	$ 77
Financing receivable, modifications, post-modification recorded investment	$ 0	$ 77	$ 0	$ 77
Nonaccrual | Term extension | Commercial real estate
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	0	0	0	0
Financing receivable, modifications, pre-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Financing receivable, modifications, post-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Nonaccrual | Term extension | Commercial non real estate
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	0	4	0	4
Financing receivable, modifications, pre-modification recorded investment	$ 0	$ 217	$ 0	$ 217
Financing receivable, modifications, post-modification recorded investment	$ 0	$ 217	$ 0	$ 217
Nonaccrual | Term extension | Agriculture
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	0	0	0	0
Financing receivable, modifications, pre-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Financing receivable, modifications, post-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Nonaccrual | Term extension | Consumer
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	0	1	0	1
Financing receivable, modifications, pre-modification recorded investment	$ 0	$ 1	$ 0	$ 1
Financing receivable, modifications, post-modification recorded investment	$ 0	$ 1	$ 0	$ 1
Nonaccrual | Payment modification | Residential real estate
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	0	0	1	0
Financing receivable, modifications, pre-modification recorded investment	$ 0	$ 0	$ 187	$ 0
Financing receivable, modifications, post-modification recorded investment	$ 0	$ 0	$ 187	$ 0
Nonaccrual | Payment modification | Commercial real estate
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	0	0	0	0
Financing receivable, modifications, pre-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Financing receivable, modifications, post-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Nonaccrual | Payment modification | Commercial non real estate
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	1	0	2	0
Financing receivable, modifications, pre-modification recorded investment	$ 364	$ 0	$ 760	$ 0
Financing receivable, modifications, post-modification recorded investment	$ 364	$ 0	$ 760	$ 0
Nonaccrual | Payment modification | Agriculture
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	0	0	0	0
Financing receivable, modifications, pre-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Financing receivable, modifications, post-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Nonaccrual | Payment modification | Consumer
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	0	0	0	0
Financing receivable, modifications, pre-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Financing receivable, modifications, post-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Nonaccrual | Bankruptcy | Residential real estate
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	0	1	0	1
Financing receivable, modifications, pre-modification recorded investment	$ 0	$ 43	$ 0	$ 43
Financing receivable, modifications, post-modification recorded investment	$ 0	$ 43	$ 0	$ 43
Nonaccrual | Bankruptcy | Commercial real estate
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	0	0	0	0
Financing receivable, modifications, pre-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Financing receivable, modifications, post-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Nonaccrual | Bankruptcy | Commercial non real estate
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	0	0	0	0
Financing receivable, modifications, pre-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Financing receivable, modifications, post-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Nonaccrual | Bankruptcy | Agriculture
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	0	0	0	0
Financing receivable, modifications, pre-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Financing receivable, modifications, post-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Nonaccrual | Bankruptcy | Consumer
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	1	0	1	0
Financing receivable, modifications, pre-modification recorded investment	$ 8	$ 0	$ 8	$ 0
Financing receivable, modifications, post-modification recorded investment	$ 8	$ 0	$ 8	$ 0
Nonaccrual | Other | Residential real estate
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	0	0	0	0
Financing receivable, modifications, pre-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Financing receivable, modifications, post-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Nonaccrual | Other | Commercial real estate
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	0	0	0	0
Financing receivable, modifications, pre-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Financing receivable, modifications, post-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Nonaccrual | Other | Commercial non real estate
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	0	0	0	0
Financing receivable, modifications, pre-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Financing receivable, modifications, post-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Nonaccrual | Other | Agriculture
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	0	0	0	0
Financing receivable, modifications, pre-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Financing receivable, modifications, post-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Nonaccrual | Other | Consumer
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | contract	0	0	0	0
Financing receivable, modifications, pre-modification recorded investment	$ 0	$ 0	$ 0	$ 0
Financing receivable, modifications, post-modification recorded investment	$ 0	$ 0	$ 0	$ 0

Loans - Subsequent Defaults on

Loans - Subsequent Defaults on Modified Loans (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2016USD ($)contract	Mar. 31, 2015USD ($)contract	Mar. 31, 2016USD ($)contract	Mar. 31, 2015USD ($)contract
Financing Receivable, Modifications [Line Items]
Number of Loans | contract	3	4	5	12
Recorded Investment | $	$ 0	$ 107	$ 372	$ 739
Residential real estate
Financing Receivable, Modifications [Line Items]
Number of Loans | contract	1	4	1	10
Recorded Investment | $	$ 0	$ 107	$ 0	$ 629
Commercial real estate
Financing Receivable, Modifications [Line Items]
Number of Loans | contract	0	0	0	0
Recorded Investment | $	$ 0	$ 0	$ 0	$ 0
Commercial non real estate
Financing Receivable, Modifications [Line Items]
Number of Loans | contract	0	0	1	1
Recorded Investment | $	$ 0	$ 0	$ 364	$ 95
Agriculture
Financing Receivable, Modifications [Line Items]
Number of Loans | contract	2	0	2	1
Recorded Investment | $	$ 0	$ 0	$ 0	$ 15
Consumer
Financing Receivable, Modifications [Line Items]
Number of Loans | contract	0	0	1	0
Recorded Investment | $	$ 0	$ 0	$ 8	$ 0

Allowance for Loan Losses - (Na

Allowance for Loan Losses - (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and written loan commitments at fair value under the fair value option	$ 1,165,660		$ 1,165,660			$ 1,118,687
Loans held for sale	5,918		5,918			9,867
Loans guaranteed by U.S. Government Agencies	6,261,747		6,261,747			6,098,475
Allowance for loan leases	61,917	$ 52,426	61,917	$ 52,426	$ 61,128	57,200	$ 51,820	$ 47,518
Net reversal of provision	1,428	1,449	2,195	3,121
Unfunded loan commitment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	400		400			400
Receivables acquired with deteriorated credit quality
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans guaranteed by U.S. Government Agencies	96,029		96,029			108,467
Allowance for loan leases	2,511		2,511			2,776
Net reversal of provision	100	$ 300	300	$ 600
Loans Guaranteed by US Government Authorities
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans guaranteed by U.S. Government Agencies	$ 129,800		$ 129,800			$ 105,000

Allowance for Loan Losses - Sum

Allowance for Loan Losses - Summary of Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2016	Mar. 31, 2015
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, beginning balance	$ 61,128	$ 51,820	$ 57,200	$ 47,518
Charge-offs	(3,270)	(10,522)	(3,998)	(11,211)
Recoveries	1,428	1,449	2,195	3,121
Provision	2,699	9,970	6,785	13,609
Allowance for loan losses, ending balance	61,917	52,426	61,917	52,426
Residential real estate
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, beginning balance	7,798	7,567	8,025	8,342
Charge-offs	(506)	(63)	(702)	(120)
Recoveries	295	70	339	113
Provision	1,218	160	1,240	(190)
Allowance for loan losses, ending balance	8,796	7,495	8,796	7,495
Commercial real estate
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, beginning balance	19,405	17,722	18,014	16,884
Charge-offs	(744)	(1,570)	(772)	(1,652)
Recoveries	409	26	491	95
Provision	1,893	(389)	3,260	346
Allowance for loan losses, ending balance	20,904	15,736	20,904	15,736
Commercial non real estate
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, beginning balance	17,160	14,625	15,996	10,550
Charge-offs	(212)	(8,440)	(257)	(8,524)
Recoveries	235	983	639	2,143
Provision	(4,552)	8,789	(3,677)	11,788
Allowance for loan losses, ending balance	12,631	15,957	12,631	15,957
Agriculture
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, beginning balance	15,473	10,920	13,952	10,655
Charge-offs	(1,113)	(27)	(1,124)	(27)
Recoveries	77	22	124	79
Provision	3,886	1,307	5,371	1,515
Allowance for loan losses, ending balance	18,323	12,222	18,323	12,222
Consumer
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, beginning balance	341	201	348	264
Charge-offs	(98)	(19)	(146)	(57)
Recoveries	45	23	70	47
Provision	48	(17)	64	(41)
Allowance for loan losses, ending balance	336	189	336	189
Other
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, beginning balance	951	785	865	823
Charge-offs	(597)	(403)	(997)	(831)
Recoveries	367	325	532	644
Provision	206	120	527	191
Allowance for loan losses, ending balance	927	827	927	827
Receivables acquired with deteriorated credit quality
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, beginning balance			2,776
Recoveries	100	300	300	600
(Improvement) impairment of loans acquired with deteriorated credit quality	(68)	(291)	(265)	(611)
Allowance for loan losses, ending balance	2,511		2,511
Receivables acquired with deteriorated credit quality | Residential real estate
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, beginning balance			1,624
(Improvement) impairment of loans acquired with deteriorated credit quality	(9)	(239)	(106)	(650)
Allowance for loan losses, ending balance	1,518		1,518
Receivables acquired with deteriorated credit quality | Commercial real estate
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, beginning balance			1,082
(Improvement) impairment of loans acquired with deteriorated credit quality	(59)	(53)	(89)	63
Allowance for loan losses, ending balance	993		993
Receivables acquired with deteriorated credit quality | Commercial non real estate
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, beginning balance			70
(Improvement) impairment of loans acquired with deteriorated credit quality	0	0	(70)	0
Allowance for loan losses, ending balance	0		0
Receivables acquired with deteriorated credit quality | Agriculture
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, beginning balance			0
(Improvement) impairment of loans acquired with deteriorated credit quality	0	0	0	0
Allowance for loan losses, ending balance	0		0
Receivables acquired with deteriorated credit quality | Consumer
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, beginning balance			0
(Improvement) impairment of loans acquired with deteriorated credit quality	0	1	0	(24)
Allowance for loan losses, ending balance	0		0
Receivables acquired with deteriorated credit quality | Other
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for loan losses, beginning balance			0
(Improvement) impairment of loans acquired with deteriorated credit quality	0	$ 0	0	$ 0
Allowance for loan losses, ending balance	$ 0		$ 0

Allowance for Loan Losses - S55

Allowance for Loan Losses - Summary of Allowance for Loan Losses by Type (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014
Financing Receivable, Allowance for Credit Losses [Line Items]
Individually evaluated for impairment	$ 23,975		$ 16,992
Collectively evaluated for impairment	35,431		37,432
Total allowance	61,917	$ 61,128	57,200	$ 52,426	$ 51,820	$ 47,518
Financing Receivables
Individually evaluated for impairment	189,274		169,504
Collectively evaluated for impairment	5,976,444		5,820,504
Loans Outstanding	6,261,747		6,098,475
Residential real estate
Financing Receivable, Allowance for Credit Losses [Line Items]
Individually evaluated for impairment	3,731		2,783
Collectively evaluated for impairment	3,547		3,618
Total allowance	8,796	7,798	8,025	7,495	7,567	8,342
Financing Receivables
Individually evaluated for impairment	12,487		13,106
Collectively evaluated for impairment	806,809		806,912
Loans Outstanding	892,074		902,207
Commercial real estate
Financing Receivable, Allowance for Credit Losses [Line Items]
Individually evaluated for impairment	7,293		4,585
Collectively evaluated for impairment	12,618		12,347
Total allowance	20,904	19,405	18,014	15,736	17,722	16,884
Financing Receivables
Individually evaluated for impairment	50,495		49,794
Collectively evaluated for impairment	2,600,323		2,385,636
Loans Outstanding	2,669,409		2,456,140
Commercial non real estate
Financing Receivable, Allowance for Credit Losses [Line Items]
Individually evaluated for impairment	5,932		5,624
Collectively evaluated for impairment	6,699		10,302
Total allowance	12,631	17,160	15,996	15,957	14,625	10,550
Financing Receivables
Individually evaluated for impairment	33,374		62,158
Collectively evaluated for impairment	1,016,396		1,056,806
Loans Outstanding	1,051,900		1,121,723
Agriculture
Financing Receivable, Allowance for Credit Losses [Line Items]
Individually evaluated for impairment	6,963		3,950
Collectively evaluated for impairment	11,360		10,002
Total allowance	18,323	15,473	13,952	12,222	10,920	10,655
Financing Receivables
Individually evaluated for impairment	92,657		44,253
Collectively evaluated for impairment	1,450,270		1,461,230
Loans Outstanding	1,544,407		1,507,021
Consumer
Financing Receivable, Allowance for Credit Losses [Line Items]
Individually evaluated for impairment	56		50
Collectively evaluated for impairment	280		298
Total allowance	336	341	348	189	201	264
Financing Receivables
Individually evaluated for impairment	261		193
Collectively evaluated for impairment	63,136		71,549
Loans Outstanding	64,447		73,013
Other
Financing Receivable, Allowance for Credit Losses [Line Items]
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	927		865
Total allowance	927	$ 951	865	$ 827	$ 785	$ 823
Financing Receivables
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	39,510		38,371
Loans Outstanding	39,510		38,371
Receivables acquired with deteriorated credit quality
Financing Receivable, Allowance for Credit Losses [Line Items]
Total allowance	2,511		2,776
Financing Receivables
Loans Outstanding	96,029		108,467
Receivables acquired with deteriorated credit quality | Residential real estate
Financing Receivable, Allowance for Credit Losses [Line Items]
Total allowance	1,518		1,624
Financing Receivables
Loans Outstanding	72,778		82,189
Receivables acquired with deteriorated credit quality | Commercial real estate
Financing Receivable, Allowance for Credit Losses [Line Items]
Total allowance	993		1,082
Financing Receivables
Loans Outstanding	18,591		20,710
Receivables acquired with deteriorated credit quality | Commercial non real estate
Financing Receivable, Allowance for Credit Losses [Line Items]
Total allowance	0		70
Financing Receivables
Loans Outstanding	2,130		2,759
Receivables acquired with deteriorated credit quality | Agriculture
Financing Receivable, Allowance for Credit Losses [Line Items]
Total allowance	0		0
Financing Receivables
Loans Outstanding	1,480		1,538
Receivables acquired with deteriorated credit quality | Consumer
Financing Receivable, Allowance for Credit Losses [Line Items]
Total allowance	0		0
Financing Receivables
Loans Outstanding	1,050		1,271
Receivables acquired with deteriorated credit quality | Other
Financing Receivable, Allowance for Credit Losses [Line Items]
Total allowance	0		0
Financing Receivables
Loans Outstanding	$ 0		$ 0

Accounting for Certain Loans 56

Accounting for Certain Loans Acquired with Deteriorated Credit Quality - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2016	Mar. 31, 2015
Receivables [Abstract]
Allowance recognized on previous impairments	$ 0.1	$ 0.4	$ 0.3	$ 0.9

Accounting for Certain Loans 57

Accounting for Certain Loans Acquired with Deteriorated Credit Quality - Schedule of Troubled Debt Restructurings (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2016	Mar. 31, 2015
Certain Loans Acquired in Transfer Accounted for as Debt Securities, Accretable Yield Movement Schedule [Roll Forward]
Balance at beginning of period	$ 41,882	$ 46,342	$ 44,489	$ 50,889
Accretion	(2,261)	(3,222)	(4,590)	(8,009)
Reclassification from (to) nonaccretable difference	222	311	(56)	631
Disposals	0	0	0	(80)
Balance at end of period	$ 39,843	$ 43,431	$ 39,843	$ 43,431

Accounting for Certain Loans 58

Accounting for Certain Loans Acquired with Deteriorated Credit Quality - Schedule of Impaired Loans (Details) - USD ($) $ in Thousands		Mar. 31, 2016	Sep. 30, 2015
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding Balance	[1]	$ 190,340	$ 204,574
Recorded Investment	[2]	96,029	108,467
Carrying Value	[3]	93,518	105,691
Residential real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding Balance	[1]	83,921	93,979
Recorded Investment	[2]	72,778	82,189
Carrying Value	[3]	71,260	80,565
Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding Balance	[1]	94,831	97,302
Recorded Investment	[2]	18,591	20,710
Carrying Value	[3]	17,598	19,628
Commercial non real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding Balance	[1]	8,957	10,387
Recorded Investment	[2]	2,130	2,759
Carrying Value	[3]	2,130	2,689
Agriculture
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding Balance	[1]	1,481	1,538
Recorded Investment	[2]	1,480	1,538
Carrying Value	[3]	1,480	1,538
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding Balance	[1]	1,150	1,368
Recorded Investment	[2]	1,050	1,271
Carrying Value	[3]	$ 1,050	$ 1,271
[1]	Represents the legal balance of loans acquired with deteriorated credit quality
[2]	Represents the book balance of loans acquired with deteriorated credit quality
[3]	Represents the book balance of loans acquired with deteriorated credit quality net of the related allowance for loan losses.

FDIC Indemnification Asset - Sc

FDIC Indemnification Asset - Schedule of Other Current Assets (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2016	Mar. 31, 2015
FDIC Indemnification Asset [Roll Forward]
Balance at beginning of period	$ 13,185	$ 22,162	$ 14,722	$ 26,678
Amortization	(895)	(2,060)	(1,927)	(4,593)
Changes in expected reimbursements from FDIC for changes in expected credit losses	1	2	(127)	(190)
Changes in reimbursable expenses	(78)	(207)	(427)	(363)
Payments (reimbursements) of covered losses from the FDIC	662	(2)	634	(1,637)
Balance at end of period	$ 12,875	$ 19,895	$ 12,875	$ 19,895

Derivative Financial Instrume60

Derivative Financial Instruments - Notional Amounts and Estimated Fair Value (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Sep. 30, 2015
Derivative [Line Items]
Positive Fair Value	$ 10	$ 41
Negative Fair Value	(74,155)	(53,559)
Termination value of net liability position	77,100
Collateral posted, amount	86,100
Liabilities | Not Designated as Hedging Instruments | Interest rate swaps
Derivative [Line Items]
Notional Amount	1,094,357	1,087,505
Positive Fair Value	10	41
Negative Fair Value	(74,155)	(53,559)
Liabilities | Not Designated as Hedging Instruments | Mortgage loan forward sale contracts
Derivative [Line Items]
Notional Amount	34,757	36,655
Positive Fair Value	0	0
Negative Fair Value	(52)	(95)
Assets | Not Designated as Hedging Instruments | Mortgage loan commitments
Derivative [Line Items]
Notional Amount	32,556	30,196
Positive Fair Value	52	95
Negative Fair Value	$ 0	$ 0

Derivative Financial Instrume61

Derivative Financial Instruments - Effect on the Consolidated Statement of Comprehensive Income (Details) - Noninterest income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2016	Mar. 31, 2015
Interest rate swaps
Derivative [Line Items]
Amount of Gain (Loss) Recognized in Income	$ (40,893)	$ (21,698)	$ (31,454)	$ (46,303)
Mortgage loan commitments
Derivative [Line Items]
Amount of Gain (Loss) Recognized in Income	76	13	52	27
Mortgage loan forward sale contracts
Derivative [Line Items]
Amount of Gain (Loss) Recognized in Income	$ (76)	$ (13)	$ (52)	$ (27)

Derivative Financial Instrume62

Derivative Financial Instruments - Offsetting Liabilities and Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Sep. 30, 2015
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative financial assets, gross amount	$ 10	$ 41
Derivative financial liabilities, gross amount	(74,155)	(53,559)
Derivative financial assets (liabilities), gross amount	(74,145)	(53,518)
Derivative financial assets, amount offset	(10)	(41)
Derivative financial liabilities, amount offset	10	41
Derivative financial assets (liabilities), Net, amount offset	0	0
Derivative financial assets, net amount presented in Consolidated Balance Sheets	0	0
Derivative financial liabilities, net amount presented in Consolidated Balance Sheets	(74,145)	(53,518)
Derivative financial assets (liabilities), net amount presented in Consolidated Balance Sheets	(74,145)	(53,518)
Derivative financial assets, Held/pledged financial instruments	0	0
Derivative financial liabilities, Held/pledged financial instruments	74,145	53,518
Derivative liabilities (assets), Net, Held/pledged financial instruments	74,145	53,518
Derivative financial asset, net amount	0	0
Derivative financial liabilities, net amount	0	0
Derivative financial assets (liabilities), net, amount offset against collateral	$ 0	$ 0

The Fair Value Option For Cer63

The Fair Value Option For Certain Loans - (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2016	Mar. 31, 2015	Sep. 30, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Eligible item for the fair value option			$ 68.8		$ 47.8
Loans greater than 90 days past due or in nonaccrual status	$ 0		0		1.5
Long-term loans and written loan commitments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Eligible item for the fair value option	(0.4)	$ (1.2)	(0.2)	$ 0.5
Fair value, option, aggregate differences, long-term debt instruments	$ 1,090		$ 1,090		$ 1,070

The Fair Value Option For Cer64

The Fair Value Option For Certain Loans - Schedule of Fair Value Option (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2016	Mar. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Change in fair value of loans	$ 35,955	$ 15,208	$ 21,054	$ 32,308
Long-term loans and written loan commitments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Change in fair value of loans	35,956	15,208	21,055	32,308
Noninterest Income | Long-term loans and written loan commitments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Change in fair value of loans	$ 35,956	$ 15,208	$ 21,055	$ 32,308

Core Deposits and Other Intan65

Core Deposits and Other Intangibles (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2016	Mar. 31, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Amortization of core deposits and other intangibles	$ 708	$ 2,313	$ 1,417	$ 4,626

Core Deposits and Other Intan66

Core Deposits and Other Intangibles - Intangible Assets Amortization Expense (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Sep. 30, 2015
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	$ 117,232	$ 117,232
Accumulated amortization	(111,530)	(110,113)
Total	5,702	7,119
Core Deposit Intangible
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	92,679	92,679
Accumulated amortization	(92,260)	(92,073)
Total	419	606
Brand Intangible
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	8,464	8,464
Accumulated amortization	(4,418)	(4,136)
Total	4,046	4,328
Customer Relationships Intangible
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	16,089	16,089
Accumulated amortization	(14,852)	(13,904)
Total	$ 1,237	$ 2,185

Core Deposits and Other Intan67

Core Deposits and Other Intangibles - Schedule of Future Amortization Expense (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Sep. 30, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Remaining in 2016	$ 1,405
2,017	1,097
2,018	564
2,019	564
2,020	564
2021 and thereafter	1,508
Total	$ 5,702	$ 7,119

Securities Sold Under Agreeme68

Securities Sold Under Agreements to Repurchase - (Narrative) (Details) - USD ($) $ in Millions	6 Months Ended
	Mar. 31, 2016	Sep. 30, 2015
Federal Funds Purchased and Securities Sold under Agreements to Repurchase [Abstract]
Securities sold under agreements to repurchase	$ 156.6	$ 180.6
Securities sold under agreements to repurchase, fair value of collateral	$ 156.7	$ 181.6
Securities sold under agreements to repurchase, collateral, percentage of borrowed funds	102.00%

Securities Sold Under Agreeme69

Securities Sold Under Agreements to Repurchase - Maturity Schedule of Agreements (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Sep. 30, 2015
Assets Sold under Agreements to Repurchase [Line Items]
Total repurchase agreements	$ 146,273	$ 185,271
US Treasury and agency securities
Assets Sold under Agreements to Repurchase [Line Items]
Total repurchase agreements	0	64,252
Mortgage-backed securities
Assets Sold under Agreements to Repurchase [Line Items]
Total repurchase agreements	146,273	121,019
Overnight and Continuous
Assets Sold under Agreements to Repurchase [Line Items]
Total repurchase agreements	143,329	182,399
Overnight and Continuous | US Treasury and agency securities
Assets Sold under Agreements to Repurchase [Line Items]
Total repurchase agreements	0	64,252
Overnight and Continuous | Mortgage-backed securities
Assets Sold under Agreements to Repurchase [Line Items]
Total repurchase agreements	143,329	118,147
Up to 30 days
Assets Sold under Agreements to Repurchase [Line Items]
Total repurchase agreements	0	0
Up to 30 days | US Treasury and agency securities
Assets Sold under Agreements to Repurchase [Line Items]
Total repurchase agreements	0	0
Up to 30 days | Mortgage-backed securities
Assets Sold under Agreements to Repurchase [Line Items]
Total repurchase agreements	0	0
30 to 90 Days
Assets Sold under Agreements to Repurchase [Line Items]
Total repurchase agreements	0	0
30 to 90 Days | US Treasury and agency securities
Assets Sold under Agreements to Repurchase [Line Items]
Total repurchase agreements	0	0
30 to 90 Days | Mortgage-backed securities
Assets Sold under Agreements to Repurchase [Line Items]
Total repurchase agreements	0	0
Greater than 90 days
Assets Sold under Agreements to Repurchase [Line Items]
Total repurchase agreements	2,944	2,872
Greater than 90 days | US Treasury and agency securities
Assets Sold under Agreements to Repurchase [Line Items]
Total repurchase agreements	0	0
Greater than 90 days | Mortgage-backed securities
Assets Sold under Agreements to Repurchase [Line Items]
Total repurchase agreements	$ 2,944	$ 2,872

FHLB Advances and Other Borro70

FHLB Advances and Other Borrowings - (Narrative) (Details) - USD ($)	6 Months Ended
	Mar. 31, 2016	Sep. 30, 2015
Debt Instrument [Line Items]
Current borrowing capacity	$ 976,800,000
Loans pledged to the Federal Home Loan Bank	2,270,000,000	$ 2,290,000,000
Wells Fargo | Revolving Credit Facility
Debt Instrument [Line Items]
Borrowing capacity	$ 10,000,000
Unused capacity fee, percentage	0.20%
Interest rate at end of period	2.44%
Outstanding advances	$ 0	$ 0
London Interbank Offered Rate (LIBOR) | Wells Fargo | Revolving Credit Facility
Debt Instrument [Line Items]
Basis spread on variable rate	2.00%

FHLB Advances and Other Borro71

FHLB Advances and Other Borrowings - Schedule of Advances, Related Party Notes (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Sep. 30, 2015
Debt Instrument [Line Items]
Notes payable to Federal Home Loan Bank (FHLB), interest rates from 0.43% to 3.66% and maturity dates from April 2016 to July 2023, collateralized by real estate loans and FHLB stock, with various call dates at the option of the FHLB	$ 370,000	$ 581,000
Notes payable to banks
Debt Instrument [Line Items]
Notes payable to Federal Home Loan Bank (FHLB), interest rates from 0.43% to 3.66% and maturity dates from April 2016 to July 2023, collateralized by real estate loans and FHLB stock, with various call dates at the option of the FHLB	$ 370,000	$ 581,000
Notes payable to banks | Minimum
Debt Instrument [Line Items]
Stated interest rate, percentage	0.43%	0.43%
Notes payable to banks | Maximum
Debt Instrument [Line Items]
Stated interest rate, percentage	3.66%	3.66%

FHLB Advances and Other Borro72

FHLB Advances and Other Borrowings - Schedule of Due or Callable Notes (Details) - FHLB Advances and Related Party Notes Payable $ in Thousands	Mar. 31, 2016USD ($)
Debt Instrument [Line Items]
Remaining in 2016	$ 60,000
2,017	25,000
2,018	25,000
2,019	0
2,020	0
2021 and thereafter	260,000
Total	$ 370,000

Profit-Sharing Plan - (Details)

Profit-Sharing Plan - (Details) - Multiple employer 401(k) profit sharing plan - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2016	Mar. 31, 2015
Defined Contribution Plan Disclosure [Line Items]
Defined contribution plan, requisite service period			1 year
Defined contribution plan, minimum age requirement			21 years
Contributions by the Company	$ 0.6	$ 0.5	$ 2	$ 1.8

Stock-Based Compensation - (Nar

Stock-Based Compensation - (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2016	Mar. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment award, award vesting period			3 years
Share-based compensation expense	$ 0.7	$ 0.2	$ 1.8	$ 0.7
Tax benefit from compensation expense	0.3	$ 0.1	$ 0.7	$ 0.3
Target performance level			100.00%
Share-based compensation, compensation cost not yet recognized	$ 5.5		$ 5.5
Share-based compensation, compensation cost not yet recognized, recognition period			2 years 8 months 13 days
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Pre-established target levels			0.00%
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Target performance level			150.00%
Pre-established target levels			150.00%
Performance shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares to be issued (approximately)			375,159
Restricted shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of vested stock awards			$ 0.7

Stock-Based Compensation - Sche

Stock-Based Compensation - Schedule of Restricted and Performance Stock (Details) - $ / shares	6 Months Ended	12 Months Ended
	Mar. 31, 2016	Sep. 30, 2015
Restricted shares
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Shares, beginning of fiscal year(shares)	80,446	0
Granted (shares)	91,896	81,419
Vested and issued (shares)	(25,526)	0
Forfeited (shares)	(1,181)	(973)
Canceled (shares)	0	0
Shares, end of period (shares)	145,635	80,446
Vested, but not issuable at end of period (shares)	24,480	12,221
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Shares, beginning of fiscal year (in USD per share)	$ 18.18	$ 0
Granted (in USD per share)	30.73	18.18
Vested and issued (in USD per share)	18.06	0
Forfeited (in USD per share)	24.69	18
Canceled (in USD per share)	0	0
Shares, end of period (in USD per share)	26.07	18.18
Vested, but not issuable at end of period (in USD per share)	$ 26.14	$ 18
Performance shares
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Shares, beginning of fiscal year(shares)	211,026	0
Granted (shares)	43,371	221,294
Vested and issued (shares)	(55)	0
Forfeited (shares)	(4,236)	(10,268)
Canceled (shares)	0	0
Shares, end of period (shares)	250,106	211,026
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Shares, beginning of fiscal year (in USD per share)	$ 18	$ 0
Granted (in USD per share)	30.78	18
Vested and issued (in USD per share)	18	0
Forfeited (in USD per share)	19.22	18
Canceled (in USD per share)	0	0
Shares, end of period (in USD per share)	$ 20.20	$ 18

Fair Value Measurements - (Narr

Fair Value Measurements - (Narrative) (Details)	6 Months Ended
	Mar. 31, 2016
Fair Value Disclosures [Abstract]
Derivative, remaining maturity (or less)	180 days

Fair Value Measurements - Sched

Fair Value Measurements - Schedule of Fair Value Measurements of Assets and Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Sep. 30, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	$ 1,328,685	$ 1,327,327
Derivatives-liabilities	74,197	53,613
Fair value loans and written loan commitments	1,165,660	1,118,687
Fair value, measurements, recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	1,328,685	1,327,327
Derivatives-assets	52	95
Derivatives-liabilities	74,197	53,613
Fair value loans and written loan commitments	1,165,660	1,118,687
Fair value, measurements, recurring | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	305,833	329,852
Derivatives-assets		0
Derivatives-liabilities	0	0
Fair value loans and written loan commitments	0	0
Fair value, measurements, recurring | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	1,021,394	995,640
Derivatives-assets	52	95
Derivatives-liabilities	74,197	53,613
Fair value loans and written loan commitments	1,165,660	1,118,687
Fair value, measurements, recurring | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	1,458	1,835
Derivatives-assets	0	0
Derivatives-liabilities	0	0
Fair value loans and written loan commitments	0	0
U.S. Treasury securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	230,837	254,797
U.S. Treasury securities | Fair value, measurements, recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	230,837	254,797
U.S. Treasury securities | Fair value, measurements, recurring | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	230,837	254,797
U.S. Treasury securities | Fair value, measurements, recurring | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	0	0
U.S. Treasury securities | Fair value, measurements, recurring | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	0	0
U.S. Agency securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	74,996	75,055
U.S. Agency securities | Fair value, measurements, recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	74,996	75,055
U.S. Agency securities | Fair value, measurements, recurring | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	74,996	75,055
U.S. Agency securities | Fair value, measurements, recurring | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	0	0
U.S. Agency securities | Fair value, measurements, recurring | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	0	0
Mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	1,015,350	989,600
Mortgage-backed securities | Fair value, measurements, recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	1,015,350	989,600
Mortgage-backed securities | Fair value, measurements, recurring | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	0	0
Mortgage-backed securities | Fair value, measurements, recurring | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	1,015,350	989,600
Mortgage-backed securities | Fair value, measurements, recurring | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	0	0
States and political subdivision securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	1,458	1,850
States and political subdivision securities | Fair value, measurements, recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	1,458	1,850
States and political subdivision securities | Fair value, measurements, recurring | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	0	0
States and political subdivision securities | Fair value, measurements, recurring | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	0	15
States and political subdivision securities | Fair value, measurements, recurring | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	1,458	1,835
Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	4,991	4,983
Corporate debt securities | Fair value, measurements, recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	4,991	4,983
Corporate debt securities | Fair value, measurements, recurring | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	0	0
Corporate debt securities | Fair value, measurements, recurring | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	4,991	4,983
Corporate debt securities | Fair value, measurements, recurring | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	0	0
Other | Fair value, measurements, recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	1,053	1,042
Other | Fair value, measurements, recurring | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	0	0
Other | Fair value, measurements, recurring | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	1,053	1,042
Other | Fair value, measurements, recurring | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	$ 0	$ 0

Fair Value Measurements - Sch78

Fair Value Measurements - Schedule of Other Available-for-Sale (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2016	Mar. 31, 2015
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	$ 1,458	$ 1,958	$ 1,835	$ 2,029
Principal paydown	0	0	(77)	(71)
Realized loss on securities	0	0	(300)	0
Ending Balance	$ 1,458	$ 1,958	$ 1,458	$ 1,958

Fair Value Measurements - Mortg

Fair Value Measurements - Mortgage Loans Held for Sale (Details) - Fair value, measurements, nonrecurring - USD ($) $ in Thousands	Mar. 31, 2016	Sep. 30, 2015
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Other real estate owned	$ 1,068	$ 8,826
Impaired loans	165,924	153,318
Loans held for sale, at lower of cost or fair value	5,918	9,867
Level 1
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Other real estate owned	0	0
Impaired loans	0	0
Loans held for sale, at lower of cost or fair value	0	0
Level 2
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Other real estate owned	0	0
Impaired loans	0	0
Loans held for sale, at lower of cost or fair value	5,918	9,867
Level 3
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Other real estate owned	1,068	8,826
Impaired loans	165,924	153,318
Loans held for sale, at lower of cost or fair value	$ 0	$ 0

Fair Value Measurements - Level

Fair Value Measurements - Level 3 Schedule (Details) - Fair value, measurements, nonrecurring - USD ($) $ in Thousands	Mar. 31, 2016	Sep. 30, 2015
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Other real estate owned	$ 1,068	$ 8,826
Impaired loans	165,924	153,318
Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Other real estate owned	1,068	8,826
Impaired loans	$ 165,924	$ 153,318

Fair Value Measurements - Sch81

Fair Value Measurements - Schedule of Balance Sheet Grouping Fair Value (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Sep. 30, 2015
Level 1 | Carrying Amount
Assets
Cash and due from banks	$ 174,401	$ 237,770
Level 1 | Fair Value
Assets
Cash and due from banks	174,401	237,770
Level 2 | Carrying Amount
Assets
Accrued interest receivable	39,487	44,077
Federal Home Loan Bank stock	27,127	35,745
Liabilities
Deposits	7,712,729	7,387,065
FHLB advances and other borrowings	370,000	581,000
Securities sold under repurchase agreements	146,273	185,271
Accrued interest payable	3,987	4,006
Subordinated debentures and subordinated notes payable	90,764	90,727
Level 2 | Fair Value
Assets
Accrued interest receivable	39,487	44,077
Federal Home Loan Bank stock	27,127	35,745
Liabilities
Deposits	7,711,376	7,385,894
FHLB advances and other borrowings	373,559	584,261
Securities sold under repurchase agreements	146,273	185,271
Accrued interest payable	3,987	4,006
Subordinated debentures and subordinated notes payable	91,764	91,305
Level 3 | Carrying Amount
Assets
Loans, net excluding fair valued loans and loans held for sale	6,324,293	6,139,444
Level 3 | Fair Value
Assets
Loans, net excluding fair valued loans and loans held for sale	$ 6,300,553	$ 6,120,262

Earnings per Share - Schedule o

Earnings per Share - Schedule of EPS, Basic and Diluted (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2016	Mar. 31, 2015
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Net income	$ 30,674	$ 19,724	$ 61,135	$ 46,421
Weighted average common shares outstanding	55,269,557	57,898,335	55,261,634	57,897,059
Dilutive effect of stock based compensation (in shares)	139,319	18,467	139,530	9,234
Weighted average common shares outstanding for diluted earnings per share calculation	55,408,876	57,916,802	55,401,164	57,906,293
Basic earnings per share (in dollars per share)	$ 0.56	$ 0.34	$ 1.11	$ 0.80
Diluted earnings per share (in dollars per share)	$ 0.55	$ 0.34	$ 1.10	$ 0.80
Performance shares
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities excluded from computation of earnings per share			36,696	30,909
Stock awards
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities excluded from computation of earnings per share			174,415	152,827