TCF Financial 10-K 23 Feb 15 2014 FY Annual report Financial data

Document_and_Entity_Informatio

Document and Entity Information (USD $)	12 Months Ended
	Dec. 31, 2014	Feb. 17, 2015	Jun. 30, 2014
Document and Entity Information
Entity Registrant Name	TCF FINANCIAL CORP
Entity Central Index Key	814184
Document Type	10-K
Document Period End Date	31-Dec-14
Amendment Flag	FALSE
Current Fiscal Year End Date	-19
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		167,692,420
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Document Fiscal Year Focus	2014
Document Fiscal Period Focus	FY
Entity Public Float			$2,468,333,703

Consolidated_Statements_of_Fin

Consolidated Statements of Financial Condition (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Assets:
Cash and due from banks	$1,115,250	$915,076
Investments	85,492	94,326
Securities held to maturity	214,454	19,912
Securities available for sale	463,294	551,064
Loans and leases held for sale	132,266	79,768
Consumer real estate:
First mortgage lien	3,139,152	3,766,421
Junior lien	2,543,212	2,572,905
Total consumer real estate	5,682,364	6,339,326
Commercial	3,157,665	3,148,352
Leasing and equipment finance	3,745,322	3,428,755
Inventory finance	1,877,090	1,664,377
Auto finance	1,915,061	1,239,386
Other	24,144	26,743
Total loans and leases	16,401,646	15,846,939
Allowance for loan and lease losses	-164,169	-252,230
Net loans and leases	16,237,477	15,594,709
Premises and equipment, net	436,361	437,602
Goodwill	225,640	225,640
Other assets	484,377	461,743
Total assets	19,394,611	18,379,840
Deposits:
Checking	5,195,243	4,980,451
Savings	5,212,320	6,194,003
Money market	1,993,130	831,910
Certificates of deposit	3,049,189	2,426,412
Total deposits	15,449,882	14,432,776
Short-term borrowings	4,425	4,918
Long-term borrowings	1,232,065	1,483,325
Total borrowings	1,236,490	1,488,243
Accrued expenses and other liabilities	572,875	494,062
Total liabilities	17,259,247	16,415,081
Equity:
Preferred stock, par value $0.01 per share, 30,000,000 shares authorized; 4,006,900 shares issued	263,240	263,240
Common stock, par value $0.01 per share, 280,000,000 shares authorized; 167,503,568 and 165,164,861 shares issued, respectively	1,675	1,652
Additional paid-in capital	817,130	779,641
Retained earnings, subject to certain restrictions	1,099,914	977,846
Accumulated other comprehensive loss	-10,910	-27,213
Treasury stock at cost, 42,566 shares, and other	-49,400	-42,198
Total TCF Financial Corporation stockholders' equity	2,121,649	1,952,968
Non-controlling interest in subsidiaries	13,715	11,791
Total equity	2,135,364	1,964,759
Total liabilities and equity	$19,394,611	$18,379,840

Consolidated_Statements_of_Fin1

Consolidated Statements of Financial Condition (Parenthetical) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Statement of Financial Position [Abstract]
Preferred stock, par value (in dollars per share)	$0.01	$0.01
Preferred stock, shares authorized	30,000,000	30,000,000
Preferred stock, shares issued	4,006,900	4,006,900
Common stock, par value (in dollars per share)	$0.01	$0.01
Common stock, shares authorized	280,000,000	280,000,000
Common stock, shares issued	167,503,568	165,164,861
Treasury stock at cost, shares	42,566	42,566

Consolidated_Statements_of_Inc

Consolidated Statements of Income (USD $)	12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Interest income:
Loans and leases	$820,436	$819,501	$835,380
Securities available for sale	11,994	18,074	35,150
Securities held to maturity	5,281	277	281
Investments and other	36,518	26,688	13,812
Total interest income	874,229	864,540	884,623
Interest expense:
Deposits	38,385	36,604	40,987
Borrowings	20,215	25,312	63,617
Total interest expense	58,600	61,916	104,604
Net interest income	815,629	802,624	780,019
Provision for credit losses	95,737	118,368	247,443
Net interest income after provision for credit losses	719,892	684,256	532,576
Non-interest income:
Fees and service charges	154,386	166,606	177,953
Card revenue	51,323	51,920	52,638
ATM revenue	22,225	22,656	24,181
Subtotal	227,934	241,182	254,772
Gains on sales of auto loans, net	43,565	29,699	22,101
Gains on sales of consumer real estate loans, net	34,794	21,692	5,413
Servicing fee income	21,444	13,406	7,759
Subtotal	99,803	64,797	35,273
Leasing and equipment finance	93,799	90,919	92,172
Other	10,704	6,196	5,974
Fees and other revenue	432,240	403,094	388,191
Gains (losses) on securities, net	1,027	964	102,232
Total non-interest income	433,267	404,058	490,423
Non-interest expense:
Compensation and employee benefits	452,942	429,188	393,841
Occupancy and equipment	139,023	134,694	130,792
FDIC insurance	25,123	32,066	30,425
Operating lease depreciation	27,152	24,500	25,378
Advertising and marketing	22,943	21,477	25,241
Other	179,904	167,777	163,897
Subtotal	847,087	809,702	769,574
Loss on termination of debt	0	0	550,735
Branch realignment	0	8,869	0
Foreclosed real estate and repossessed assets, net	24,567	27,950	41,358
Other credit costs, net	123	-1,252	887
Total non-interest expense	871,777	845,269	1,362,554
Income (loss) before income tax expense (benefit)	281,382	243,045	-339,555
Income tax expense (benefit)	99,766	84,345	-132,858
Income after income tax expense	181,616	158,700	-206,697
Income attributable to non-controlling interest	7,429	7,032	6,187
Net income (loss) attributable to TCF Financial Corporation	174,187	151,668	-212,884
Preferred stock dividends	19,388	19,065	5,606
Net income (loss) available to common stockholders	$154,799	$132,603	($218,490)
Net income (loss) per common share:
Basic (in dollars per share)	$0.95	$0.82	($1.37)
Diluted (in dollars per share)	$0.94	$0.82	($1.37)

Consolidated_Statements_of_Com

Consolidated Statements of Comprehensive Income (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Statement of Comprehensive Income [Abstract]
Net income (loss) attributable to TCF Financial Corporation	$174,187	$151,668	($212,884)
Securities available for sale:
Unrealized gains (losses) arising during the period	29,071	-61,177	19,794
Reclassification of net (gains) losses to net income (loss)	-76	-860	-89,879
Net investment hedge:
Unrealized gains (losses) arising during the period	3,126	1,625	-630
Foreign currency translation adjustment:
Unrealized gains (losses) arising during the period	-3,704	-1,979	531
Recognized postretirement prior service cost:
Unrealized gains (losses) arising during the period	0	0	151
Reclassification of net (gains) losses to net income (loss)	-47	-46	-28
Income tax (expense) benefit	-12,067	22,781	25,678
Total other comprehensive income (loss)	16,303	-39,656	-44,383
Comprehensive income (loss)	$190,490	$112,012	($257,267)

Consolidated_Statements_of_Equ

Consolidated Statements of Equity (USD $)	Total	TCF Financial Corporation	Preferred Stock	Common Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive (Loss) Income	Treasury Stock and Other	Non-controlling Interests
In Thousands, except Share data, unless otherwise specified
Balance at Dec. 31, 2011	$1,878,627	$1,868,133	$0	$1,604	$715,247	$1,127,823	$56,826	($33,367)	$10,494
Balance (in shares) at Dec. 31, 2011			0	160,366,380
Increase (Decrease) in Equity
Net income (loss) attributable to TCF Financial Corporation	-206,697	-212,884				-212,884			6,187
Other comprehensive income (loss)	-44,383	-44,383					-44,383
Public offering of preferred stock	263,240	263,240	263,240
Public offering of preferred stock (in shares)			4,006,900
Net investment by (distribution to) non-controlling interest	-3,411								-3,411
Dividends on preferred stock	-5,606	-5,606				-5,606
Dividends on common stock	-31,904	-31,904				-31,904
Grants of restricted stock	0	0		18	-18
Grants of restricted stock (in shares)				1,822,025
Common shares purchased by TCF employee benefit plans	19,462	19,462		17	19,445
Common shares purchased by TCF employee benefit plans (in shares)				1,742,990
Cancellation of shares of restricted stock	-1,185	-1,185		-3	-1,198	16
Cancellation of shares of restricted stock (in shares)				-322,908
Cancellation of common shares for tax withholding	-1,949	-1,949		-2	-1,947
Cancellation of common shares for tax withholding (in shares)				-179,724
Net amortization of stock compensation	11,108	11,108			11,108
Stock compensation tax (expense) benefit					-659
Stock compensation tax (expense) benefit	-659	-659
Change in shares held in trust for deferred compensation plans, at cost					8,062			-8,062
Balance at Dec. 31, 2012	1,876,643	1,863,373	263,240	1,634	750,040	877,445	12,443	-41,429	13,270
Balance (in shares) at Dec. 31, 2012			4,006,900	163,428,763
Increase (Decrease) in Equity
Net income (loss) attributable to TCF Financial Corporation	158,700	151,668				151,668			7,032
Other comprehensive income (loss)	-39,656	-39,656					-39,656
Net investment by (distribution to) non-controlling interest	-8,511								-8,511
Dividends on preferred stock	-19,065	-19,065				-19,065
Dividends on common stock	-32,227	-32,227				-32,227
Grants of restricted stock	0	0		5	-5
Grants of restricted stock (in shares)				532,777
Common shares purchased by TCF employee benefit plans	20,179	20,179		14	20,165
Common shares purchased by TCF employee benefit plans (in shares)				1,389,819
Cancellation of shares of restricted stock	-274	-274			-299	25
Cancellation of shares of restricted stock (in shares)				-120,313
Cancellation of common shares for tax withholding	-955	-955		-1	-954
Cancellation of common shares for tax withholding (in shares)				-66,185
Net amortization of stock compensation	10,398	10,398			10,398
Stock compensation tax (expense) benefit					-473
Stock compensation tax (expense) benefit	-473	-473
Change in shares held in trust for deferred compensation plans, at cost					769			-769
Balance at Dec. 31, 2013	1,964,759	1,952,968	263,240	1,652	779,641	977,846	-27,213	-42,198	11,791
Balance (in shares) at Dec. 31, 2013			4,006,900	165,164,861
Increase (Decrease) in Equity
Net income (loss) attributable to TCF Financial Corporation	181,616	174,187				174,187			7,429
Other comprehensive income (loss)	16,303	16,303					16,303
Net investment by (distribution to) non-controlling interest	-5,505								-5,505
Dividends on preferred stock	-19,388	-19,388				-19,388
Dividends on common stock	-32,731	-32,731				-32,731
Grants of restricted stock	0	0		11	-11
Grants of restricted stock (in shares)				1,152,906
Common shares purchased by TCF employee benefit plans	23,083	23,083		15	23,068
Common shares purchased by TCF employee benefit plans (in shares)				1,452,837
Cancellation of shares of restricted stock	-520	-520		-1	-519
Cancellation of shares of restricted stock (in shares)				-108,490
Cancellation of common shares for tax withholding	-3,334	-3,334		-2	-3,332
Cancellation of common shares for tax withholding (in shares)				-205,546
Net amortization of stock compensation	9,025	9,025			9,025
Stock compensation tax (expense) benefit					1,316
Exercise of stock options	740	740		0	740
Exercise of stock options (in shares)				47,000
Stock compensation tax (expense) benefit	1,316	1,316
Change in shares held in trust for deferred compensation plans, at cost					7,202			-7,202
Balance at Dec. 31, 2014	$2,135,364	$2,121,649	$263,240	$1,675	$817,130	$1,099,914	($10,910)	($49,400)	$13,715
Balance (in shares) at Dec. 31, 2014			4,006,900	167,503,568

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Cash flows from operating activities:
Net income (loss) attributable to TCF Financial Corporation	$174,187	$151,668	($212,884)
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for credit losses	95,737	118,368	247,443
Depreciation and amortization	128,701	117,950	109,192
Proceeds from sales of loans and leases held for sale	571,551	277,180	161,221
Gains on sales of assets, net	90,736	61,265	140,665
Loss on termination of debt	0	0	550,735
Net income attributable to non-controlling interest	7,429	7,032	6,187
Originations of loans held for sale, net of repayments	-626,172	-353,982	-171,420
Net increase in other assets and accrued expenses and other liabilities	83,624	190,371	-67,985
Other, net	-32,571	-36,288	14,839
Net cash provided by (used in) operating activities	311,750	411,034	496,663
Cash flows from investing activities:
Loan originations and purchases, net of principal collected on loans and leases	-2,190,753	-1,196,030	-1,353,981
Purchases of equipment for lease financing	-920,985	-904,383	-938,228
Purchase of inventory finance portfolios	0	-9,658	-37,527
Proceeds from sales of loans	2,278,812	1,378,235	560,421
Proceeds from sales of lease receivables	25,468	43,215	78,805
Proceeds from sales of securities	2,813	46,506	2,089,044
Purchases of securities	139,080	53,312	645,880
Proceeds from Maturities, Prepayments and Calls of Marketable Securities	58,151	91,424	202,900
Purchases of Federal Home Loan Bank stock	-97,000	-18,789	-157,517
Redemption of Federal Home Loan Bank stock	105,931	40,976	197,571
Proceeds from sales of real estate owned	67,049	102,250	132,044
Purchases of premises and equipment	-45,469	-37,859	-44,082
Other, net	30,140	35,636	39,949
Net cash provided by (used in) investing activities	-824,923	-481,789	123,519
Cash flows from financing activities:
Net increase in deposits	997,661	370,356	1,848,782
Net change in short-term borrowings	-493	2,299	-3,797
Proceeds from long-term borrowings	2,808,612	744,348	1,283,466
Payments on long-term borrowings	-3,009,948	-1,120,402	-4,164,102
Net proceeds from public offerings of preferred stock	0	0	263,240
Redemption of subordinated debt	-50,000	-71,020	0
Redemption of trust preferred securities	0	0	-115,010
Net investment by (distribution to) non-controlling interest	-5,505	-8,511	-3,411
Dividends paid on preferred stock	-19,388	-19,065	-5,606
Dividends paid on common stock	-32,731	-32,227	-31,904
Stock compensation tax (expense) benefit	1,316	-473	-659
Common shares sold to TCF employee benefit plans	23,083	20,179	19,462
Exercise of stock options	740	0	0
Net cash provided by (used in) financing activities	713,347	-114,516	-909,539
Net change in cash and due from banks	200,174	-185,271	-289,357
Cash and due from banks at beginning of period	915,076	1,100,347	1,389,704
Cash and due from banks at end of period	1,115,250	915,076	1,100,347
Cash paid (received) for:
Interest on deposits and borrowings	55,954	61,453	108,524
Income taxes, net	113,562	-28,456	-13,376
Transfer of loans to other assets	91,180	112,463	137,311
Transfer of securities available for sale to securities held to maturity	$191,665	$9,342	$0

Summary_of_Significant_Account

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2014
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies
	Basis of Presentation TCF Financial Corporation, a Delaware corporation ("we," "us," "our," "TCF" or the "Company"), is a national bank holding company based in Wayzata, Minnesota. Unless otherwise indicated, references herein to "TCF" include its direct and indirect subsidiaries. Its principal subsidiary, TCF National Bank ("TCF Bank"), is headquartered in South Dakota. References herein to "TCF Financial" refer to TCF Financial Corporation on an unconsolidated basis. All significant intercompany accounts and transactions have been eliminated in consolidation.
	Certain reclassifications have been made to prior period financial statements to conform to the current period presentation.
	The preparation of financial statements in conformity with U.S. generally accepted accounting principles ("GAAP") requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities at the date of the financial statements and the reported amount of revenues and expenses during the reporting period. These estimates are based on information available to management at the time the estimates are made. Actual results could differ from those estimates.
	Critical Accounting Policies
	Critical Accounting Estimates Critical accounting estimates occur in certain accounting policies and procedures and are particularly susceptible to significant change. Policies that contain critical accounting estimates include the determination of the allowance for loan and lease losses, lease financing and income taxes.
	Allowance for Loan and Lease Losses The allowance for loan and lease losses is maintained at a level appropriate to provide for probable loan and lease losses incurred in the portfolio as of the balance sheet date, including known or anticipated problem loans and leases, as well as for loans and leases which are not currently known to require specific allowances. Loans classified as troubled debt restructuring ("TDR") loans are considered impaired loans. TCF individually evaluates impairment on all impaired commercial and inventory finance loans, certain large impaired equipment finance loans and leases, large consumer real estate TDR loans, auto finance TDR loans and all non-accrual Winthrop Resources Corporation ("Winthrop") leases. All other loans and leases are evaluated collectively for impairment. See Note 6, Allowance for Loan and Lease Losses and Credit Quality Information, for a definition of impaired loans.
	Loan impairment on consumer real estate TDR loans is a key component of the allowance for loan and lease losses. Impairment is generally based upon the present value of the expected future cash flows discounted at the loan's initial effective interest rate, unless the loans are collateral dependent, in which case loan impairment is based upon the fair value of the collateral less selling expenses. See Note 6, Allowance for Loan and Lease Losses and Credit Quality Information, for further information on the determination of the allowance for losses on accruing consumer real estate TDR loans.
	Loan impairment on commercial, equipment finance and inventory finance loans is generally based upon the present value of the expected future cash flows discounted at the loan's initial effective interest rate, unless the loans are collateral dependent, in which case loan impairment is based upon the fair value of collateral less estimated selling costs; however, if payment or satisfaction of the loan is dependent on the operation, rather than the sale of the collateral, the impairment does not include selling costs.
	The impairment for all other loans and leases is evaluated collectively by various characteristics. The collective evaluation of incurred losses in these portfolios is based upon their historical loss rates multiplied by the respective loss emergence period. Factors utilized in the determination of the amount of the allowance include historical trends in loss rates, the portfolio's overall risk characteristics, changes in its character or size, risk rating migration, delinquencies, collateral values and prevailing economic conditions.
	Loans and leases are charged off to the extent they are deemed to be uncollectible. Charge-offs related to confirmed losses are utilized in the historical data in calculating the allowance for loan and lease losses. Consumer real estate loans are charged off to the estimated fair value of underlying collateral, less estimated selling costs, no later than 150 days past due. Additional review of the fair value, less estimated costs to sell, compared with the recorded value occurs upon foreclosure and additional charge-offs are recorded if necessary. Auto finance loans are generally charged off to the estimated fair value of underlying collateral, less estimated selling costs, if repossession is reasonably assured and in process. Otherwise, auto finance loans are charged off in full no later than 120 days past due. Deposit account overdrafts, which are included within other loans, are charged off at or before they are 60 days past due. Commercial loans, leasing and equipment finance loans and inventory finance loans which are considered collateral dependent are charged off to estimated fair value, less estimated selling costs when it becomes probable, based on current information and events, that all principal and interest amounts will not be collectible in accordance with contractual terms. Loans which are not collateral dependent are charged off when deemed uncollectible based on specific facts and circumstances.
	The amount of the allowance for loan and lease losses significantly depends upon management's estimates of variables affecting valuation, appraisals of collateral, evaluations of performance and status and the amounts and timing of future cash flows expected to be received. Such estimates, appraisals, evaluations and cash flows may be subject to frequent adjustments due to changing economic prospects of borrowers, lessees or properties. These estimates are reviewed periodically and adjustments, if necessary, are recorded in the provision for credit losses in the periods in which they become known.
	Lease Financing TCF provides various types of commercial lease financing that are classified for accounting purposes as direct financing, sales-type or operating leases. Leases that transfer substantially all of the benefits and risks of ownership to the lessee are classified as direct financing or sales-type leases and are included in loans and leases. Direct financing and sales-type leases are carried at the combined present value of future minimum lease payments and lease residual values. The determination of lease classification requires various judgments and estimates by management including the fair value of the equipment at lease inception, useful life of the equipment under lease, estimate of the lease residual value and collectability of minimum lease payments.
	Sales-type leases generate dealer profit which is recognized at lease inception by recording lease revenue net of lease cost. Lease revenue consists of the present value of the future minimum lease payments. Lease cost consists of the leased equipment's book value, less the present value of its residual. Interest income on direct financing and sales-type leases is recognized using methods which approximate a level yield over the fixed, non-cancelable term of the lease. TCF receives pro rata rent payments for the interim period until the lease contract commences and the fixed, non-cancelable lease term begins. TCF recognizes these interim payments in the month they are earned and records the income in interest income on direct finance leases. Management has policies and procedures in place for the determination of lease classification and review of the related judgments and estimates for all lease financings.
	Some lease financings include a residual value component, which represents the estimated fair value of the leased equipment at the expiration of the initial term of the transaction. The estimation of residual values involves judgment regarding product and technology changes, customer behavior, shifts in supply and demand and other economic assumptions. TCF reviews residual assumptions on the portfolio at least annually and downward adjustments, if necessary, are charged to non-interest expense in the periods in which they become known.
	TCF occasionally sells minimum lease payments as a credit risk reduction tool to third-party financial institutions at fixed rates on a non-recourse basis with its underlying equipment as collateral. For those transactions which achieve sale treatment, the related lease cash flow stream and the non-recourse financing are derecognized. For those transactions which do not achieve sale treatment, the underlying lease remains on TCF's Consolidated Statements of Financial Condition and non-recourse debt is recorded in the amount of the proceeds received. TCF retains servicing of these leases and bills, collects and remits funds to the third-party financial institution. Upon default by the lessee, the third-party financial institutions may take control of the underlying collateral which TCF would otherwise retain as residual value.
	Leases which do not transfer substantially all benefits and risks of ownership to the lessee are classified as operating leases. Such leased equipment and related initial direct costs are included in other assets on the Consolidated Statements of Financial Condition and depreciated on a straight-line basis over the term of the lease to its estimated salvage value. Depreciation expense is recorded as operating lease expense and included in non-interest expense. Operating lease rental income is recognized when it is due and is reflected as a component of non-interest income. An allowance for lease losses is not provided on operating leases.
	Income Taxes Income taxes are accounted for using the asset and liability method. Under this method, deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax basis carrying amounts. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period in which the enactment date occurs. Also, if current period income tax rates change, the impact on the annual effective income tax rate is applied year-to-date in the period of enactment.
	The determination of current and deferred income taxes is a critical accounting estimate which is based on complex analyses of many factors, including interpretation of income tax laws, the evaluation of uncertain tax positions, differences between the tax and financial reporting bases of assets and liabilities (temporary differences), estimates of amounts due or owed, the timing of reversals of temporary differences and current financial accounting standards. Additionally, there can be no assurance that estimates and interpretations used in determining income tax liabilities will not be challenged by taxing authorities. Actual results could differ significantly from the estimates and tax law interpretations used in determining the current and deferred income tax liabilities.
	In the preparation of income tax returns, tax positions are taken based on interpretation of income tax laws for which the outcome is uncertain. Management periodically reviews and evaluates the status of uncertain tax positions and makes estimates of amounts ultimately due or owed. The benefits of tax positions are recorded in income tax expense in the Consolidated Statements of Income, net of the estimates of ultimate amounts due or owed, including any applicable interest and penalties. Changes in the estimated amounts due or owed may result from closing of the statute of limitations on tax returns, new legislation, clarification of existing legislation through government pronouncements, judicial action and through the examination process. TCF's policy is to report interest and penalties, if any, related to unrecognized tax benefits in income tax expense in the Consolidated Statements of Income.
	Other Significant Accounting Policies
	Investments Investments are carried at cost. TCF periodically evaluates investments for other than temporary impairment with losses, if any, recorded in non-interest income within gains (losses) on securities, net.
	Securities Held to Maturity Securities held to maturity are carried at cost and adjusted for amortization of premiums or accretion of discounts using a level yield method; however, transfers of securities available for sale to securities held to maturity are made at fair value at the date of transfer. The unrealized holding gain or loss at the date of each transfer is retained in accumulated other comprehensive income (loss) and in the carrying value of the held to maturity investment security. Such amounts are then amortized over the remaining life of the transferred security as an adjustment of the yield on those securities. TCF periodically evaluates securities held to maturity for other than temporary impairment. Declines in value considered other than temporary, if any, would be recorded as non-interest income within gains (losses) on securities, net.
	Securities Available for Sale Securities available for sale are carried at fair value with the unrealized gains or losses, net of related deferred income taxes, reported within accumulated other comprehensive income (loss), a separate component of equity. The cost of securities sold is determined on a specific identification basis and gains or losses on sales of securities available for sale are recognized on trade dates. TCF evaluates securities available for sale for other than temporary impairment on a quarterly basis. Declines in the value of securities available for sale that are considered other than temporary are recorded in non-interest income within gains (losses) on securities, net. Discounts and premiums on securities available for sale are amortized using a level yield method over the expected life of the security.
	Loans and Leases Held for Sale Loans and leases designated as held for sale are carried at the lower of cost or fair value. Any amount by which cost exceeds fair value is initially recorded as a valuation allowance and subsequently reflected in the gain or loss on sale when sold. From time to time, management identifies and designates primarily consumer real estate and auto finance loans held in the loan portfolios for sale. These loans are transferred to loans and leases held for sale at the lower of cost or fair market value at the time of transfer. Any associated allowance for loan and lease losses is transferred to the valuation allowance.
	Loans and Leases Loans and leases are reported at historical cost including net direct fees and costs associated with originating and acquiring loans and leases. The net direct fees and costs for sales-type leases are offset against revenues recorded at the commencement of sales-type leases. Discounts and premiums on acquired loans, net direct fees and costs, unearned discounts and finance charges and unearned lease income are amortized to interest income using methods which approximate a level yield over the estimated remaining lives of the loans and leases. Net direct fees and costs on all lines of credit are amortized on a straight line basis over the contractual life of the line of credit and adjusted for payoffs. Net deferred fees and costs on consumer real estate lines of credit are amortized to service fee income.
	Non-accrual Loans and Leases Loans and leases are generally placed on non-accrual status when the collection of interest and principal is 90 days or more past due unless, in the case of commercial loans, they are well-secured and in the process of collection. Auto loans are placed on non-accrual status when interest and principal is 120 days past due. Delinquent junior lien loans are also placed on non-accrual status when there is evidence that the related third-party first lien mortgage may be 90 days or more past due.
	Loans on non-accrual status are generally reported as non-accrual loans until there is sustained repayment performance for six consecutive months, with the exception of loans not reaffirmed upon discharge under Chapter 7 bankruptcy, which remain on non-accrual status until TCF expects full repayment of the remaining pre-discharged contractual principal and interest. Income on these loans is recognized on a cash basis when there is sustained repayment performance for six consecutive months, the loan is not more than 60 days delinquent and a current credit evaluation has been completed.
	Generally, when a loan or lease is placed on non-accrual status, uncollected interest accrued in prior years is charged-off against the allowance for loan and lease losses and interest accrued in the current year is reversed against interest income. For non-accrual leases that have been discounted with third-party financial institutions on a non-recourse basis, the related liability is also placed on non-accrual status. Interest payments received on loans and leases in non-accrual status are generally applied to principal unless the remaining principal balance has been determined to be fully collectible, in which case interest income is recognized on a cash basis.
	Premises and Equipment Premises and equipment, including leasehold improvements, are carried at cost and are depreciated or amortized on a straight-line basis over estimated useful lives of owned assets and for leasehold improvements over the estimated useful life of the related asset or the lease term, whichever is shorter. Maintenance and repairs are charged to expense as incurred. Rent expense for leased land with facilities is recognized in occupancy and equipment expense. Rent expense for leases with free rent periods or scheduled rent increases is recognized on a straight-line basis over the lease term.
	Other Real Estate Owned and Repossessed and Returned Assets Assets acquired through foreclosure, repossession or returned to TCF are initially recorded at the lower of the loan or lease carrying amount or fair value of the collateral less estimated selling costs at the time of transfer to real estate owned or repossessed and returned assets. The fair value of other real estate owned is based on independent appraisals, real estate brokers' price opinions or automated valuation methods, less estimated selling costs. The fair value of repossessed and returned assets is based on available pricing guides, auction results or price opinions, less estimated selling costs. Any carrying amount in excess of the fair value less estimated selling costs is charged off to the allowance for loan and lease losses. Subsequently, if the fair value of an asset, less the estimated costs to sell, declines to less than the carrying amount of the asset, the shortfall is recognized in the period in which it becomes known and is included in foreclosed real estate and repossessed assets, net expense. Operating expenses of properties and recoveries on sales of other real estate owned are also recorded in foreclosed real estate and repossessed assets, net. Operating revenue from foreclosed property is included in other non-interest income. Other real estate owned at December 31, 2014 and 2013, was $65.7 million and $68.9 million, respectively. Repossessed and returned assets at both December 31, 2014 and 2013, was $3.5 million.
	Investments in Affordable Housing Limited Partnerships Investments in affordable housing consist of investments in limited partnerships that operate qualified affordable housing projects or that invest in other limited partnerships formed to operate affordable housing projects. TCF generally utilizes the effective yield method to account for these investments with the tax credits and amortization of the investment reflected in the Consolidated Statements of Income as a reduction of income tax expense. However, depending on circumstances, the equity or cost methods may be utilized. The amount of the investment along with any unfunded equity contributions which are unconditional and legally binding are recorded in other assets. A liability for the unfunded equity contributions is recorded in other liabilities.
	Interest-Only Strips TCF periodically sells loans to third party financial institutions at fixed or variable rates. For those transactions which achieve sale treatment, the underlying loan is not recognized on TCF's Consolidated Statements of Financial Condition. The Company sells these loans at par value and generally retains an interest in the future cash flows of borrower loan payments, known as an interest-only strip. The interest-only strip is recorded at fair value at the time of sale. The fair value of the interest-only strip represents the present value of future cash flows generated by the loans to be retained by TCF. After initial recording of the interest-only strip, the accretable yield is measured as the difference between the initial investment, or fair value, and the cash flows expected to be collected. The accretable yield is amortized into interest income over the life of the interest-only strip using the effective yield method. The expected cash flows are evaluated quarterly to determine if they have changed from previous projections. If the present value of the original cash flows expected to be collected is less than the present value of the current estimate of cash flows to be collected, the change is adjusted prospectively over the remaining life of the interest-only strip. If the present value of the original cash flows expected to be collected is greater than the present value of the current estimate, an other than temporary impairment is generally recorded.
	Intangible Assets All assets and liabilities acquired in purchase acquisitions, including goodwill and other intangibles, are recorded at fair value. Goodwill is recorded when the purchase price of an acquisition is greater than the fair value of net assets, including identifiable intangible assets. Goodwill is not amortized, but assessed for impairment on an annual basis at the reporting unit level. Interim impairment analysis may be required if events occur or circumstances change that would more likely than not reduce a reporting unit's fair value below its carrying amount. Other intangible assets are amortized on a straight-line or effective yield basis over their estimated useful lives and are subject to impairment if events or circumstances indicate a possible inability to realize their carrying amounts.
	When testing for goodwill impairment, TCF initially performs a qualitative assessment. Based on the results of this qualitative assessment, if TCF concludes it is more likely than not that a reporting unit's fair value is less than its carrying amount, a quantitative analysis is performed. Quantitative valuation methodologies primarily include discounted cash flow analysis in determining fair value of reporting units. If the fair value is less than the carrying amount, additional analysis is required to measure the amount of impairment. Impairment losses, if any, are recorded as a charge to non-interest expense and an adjustment to the carrying value of goodwill.
	Other intangible assets are reviewed for impairment whenever events or changes in circumstances indicate their carrying amount may not be recoverable. Impairment is indicated if the sum of the undiscounted estimated future net cash flows is less than the carrying value of the intangible asset. Impairment losses, if any, permanently reduce the carrying value of the other intangible assets.
	Stock-Based Compensation The fair value of restricted stock and stock options is determined on the date of grant and amortized to compensation expense, with a corresponding increase in additional paid-in capital, over the longer of the service period or performance period, but in no event beyond an employee's retirement date or date of employment termination. For performance-based restricted stock, TCF estimates the degree to which performance conditions will be met to determine the number of shares that will vest and the related compensation expense. Compensation expense is adjusted in the period such estimates change. Non-forfeitable dividends, if any, paid on shares of restricted stock are recorded to retained earnings for shares that are expected to vest and to compensation expense for shares that are not expected to vest.
	Income tax benefits related to stock compensation, in excess of grant date fair value less any proceeds on exercise, are recognized as additional paid-in capital upon vesting or exercise and delivery of the stock. Any income tax benefits that are less than grant date fair value less any proceeds on exercise are recognized as a reduction of additional paid in capital to the extent of previously recognized income tax benefits and then as income tax expense for any remaining amount. See Note 15, Stock Compensation, for additional information concerning stock-based compensation.
	Deposit Account Overdrafts Deposit account overdrafts are reported in other loans and leases. Net losses on uncollectible overdrafts are reported as net charge-offs in the allowance for loan and lease losses within 60 days from the date of overdraft. Uncollectible deposit fees are reversed against fees and service charges and a related reserve for uncollectible deposit fees is maintained in other liabilities. Other deposit account losses are reported in other non-interest expense.

Cash_and_Due_from_Banks

Cash and Due from Banks	12 Months Ended
	Dec. 31, 2014
Cash and Cash Equivalents [Abstract]
Cash and Due from Banks	Cash and Due from Banks
	At December 31, 2014 and 2013, TCF Bank was required by Federal Reserve regulations to maintain reserves of $98.7 million and $95.5 million, respectively, in cash on hand or at the Federal Reserve Bank.
	TCF maintains cash balances that are restricted as to their use in accordance with certain contractual agreements primarily related to the sale and servicing of auto loans and consumer real estate loans. Cash payments received on loans serviced for third parties are held in separate accounts until remitted. TCF also retains cash balances for potential loss recourse on certain sold auto loans as well as cash for collateral on certain borrowings, foreign exchange contracts and interest rate contracts. TCF maintained restricted cash totaling $67.8 million and $46.1 million at December 31, 2014 and 2013, respectively.
	TCF had cash held in interest-bearing accounts of $842.1 million and $613.3 million at December 31, 2014 and 2013, respectively.

Investments

Investments	12 Months Ended
	Dec. 31, 2014
Investments
Investments	Investments
	Investments consisted of the following.
		At December 31,
	(In thousands)	2014		2013
	Federal Home Loan Bank stock, at cost	$	47,914	$	56,845
	Federal Reserve Bank stock, at cost	37,578		37,481
	Total investments	$	85,492	$	94,326
	The investments in Federal Home Loan Bank stock are required investments related to TCF's membership in and current borrowings from the Federal Home Loan Bank ("FHLB") of Des Moines. All Federal Home Loan Banks ("FHLBanks") obtain their funding primarily through issuance of consolidated obligations of the FHLB system. The U.S. Government does not guarantee these obligations and each of the 12 FHLBanks are jointly and severally liable for repayment of each other's debt. Therefore, TCF's investments in FHLB of Des Moines could be adversely impacted by the financial operations of the FHLBanks and actions of their regulator, the Federal Housing Finance Agency.
	TCF Bank is required to hold Federal Reserve Bank stock equal to 6% of TCF Bank's capital surplus, which is defined as additional paid-in capital stock, less any deficit retained earnings, gains (losses) on available for sale securities and foreign currency translation adjustments as of the current period end.
	The yield on investments, which have no stated contractual maturity, is 4.25% and 3.93% at December 31, 2014 and 2013, respectively.

Securities_Available_for_Sale_

Securities Available for Sale and Securities Held to Maturity	12 Months Ended
	Dec. 31, 2014
Investments, Debt and Equity Securities [Abstract]
Securities Available for Sale and Securities Held to Maturity	Securities Available for Sale and Securities Held to Maturity
	Securities consisted of the following.
		At December 31,
		2014											2013
	(Dollars in thousands)	Amortized			Gross		Gross			Fair			Amortized				Gross		Gross		Fair
		Cost			Unrealized		Unrealized			Value			Cost				Unrealized		Unrealized		Value
					Gains		Losses										Gains		Losses
	Securities available for sale:
	Mortgage-backed securities:
	U.S. Government sponsored enterprises and federal agencies	$	461,575		$	2,405	$	741		$	463,239		$	592,283			$	1,131	$	45,377	$	548,037
	Other	55			—		—			55			93				—		—		93
	Other securities	—			—		—			—			1,642				1,292		—		2,934
	Total securities available for sale	$	461,630		$	2,405	$	741		$	463,294		$	594,018			$	2,423	$	45,377	$	551,064
	Weighted-average yield	2.62		%									2.65		%
	Securities held to maturity:
	Mortgage-backed securities:
	U.S. Government sponsored enterprises and federal agencies	$	209,538		$	7,988	$	109		$	217,417		$	14,610			$	—	$	—	$	14,610
	Other securities	4,916			—		—			4,916			5,302				—		—		5,302
	Total securities held to maturity	$	214,454		$	7,988	$	109		$	222,333		$	19,912			$	—	$	—	$	19,912
	Weighted-average yield	2.64		%									3.43		%
	Gross realized gains of $1.2 million, $1.2 million and $90.2 million were recognized on sales of securities available for sale during 2014, 2013 and 2012, respectively. At December 31, 2014 and 2013, mortgage-backed securities with a carrying value of $8.2 million and $14.7 million, respectively, were pledged as collateral to secure certain deposits and borrowings. There were no impairment charges recognized on securities available for sale during 2014 or 2013. During 2012, TCF recorded impairment charges of $0.2 million on other securities as full recovery was not expected.
	Unrealized losses on securities available for sale are due to changes in interest rates. TCF has the ability and intent to hold these investments until a recovery of fair value occurs.
	During 2014 and 2013, TCF transferred $191.7 million and $9.3 million, respectively, of available for sale mortgage-backed securities to held to maturity, reflecting TCF's intent and ability to hold these securities to maturity. At December 31, 2014 and 2013, the unrealized holding loss on the transferred securities retained in accumulated other comprehensive loss totaled $16.0 million and $0.3 million, respectively. These amounts are amortized over the remaining life of the transferred security. Other held to maturity securities consist primarily of non-trading mortgage-backed securities and other bonds which qualify for investment credit under the Community Reinvestment Act. During 2014, 2013 and 2012, TCF recorded an impairment charge of $0.1 million, $0.2 million and $0.9 million, respectively, on held to maturity securities, which had a carrying value of $4.9 million, $5.3 million and $5.7 million at December 31, 2014, 2013 and 2012, respectively.
	The following tables show the gross unrealized losses and fair value of securities available for sale at December 31, 2014 and 2013 and securities held to maturity at December 31, 2014, aggregated by investment category and the length of time the securities were in a continuous loss position. There were no gross unrealized losses for securities held to maturity at December 31, 2013.
		At December 31, 2014
		Less than 12 months					12 months or more						Total
	(In thousands)	Fair Value			Unrealized		Fair Value			Unrealized			Fair Value				Unrealized
					Losses					Losses							Losses
	Securities available for sale:
	Mortgage-backed securities:
	U.S. Government sponsored enterprises and federal agencies	$	—		$	—	$	198,550		$	741		$	198,550			$	741
	Total securities available for sale	$	—		$	—	$	198,550		$	741		$	198,550			$	741
	Securities held to maturity:
	Mortgage-backed securities:
	U.S. Government sponsored enterprises and federal agencies	$	2,602		$	109	$	—		$	—		$	2,602			$	109
	Total securities held to maturity	$	2,602		$	109	$	—		$	—		$	2,602			$	109
		At December 31, 2013
		Less than 12 months					12 months or more						Total
	(In thousands)	Fair Value			Unrealized		Fair Value			Unrealized			Fair Value				Unrealized
					Losses					Losses							Losses
	Securities available for sale:
	Mortgage-backed securities:
	U.S. Government sponsored enterprises and federal agencies	$	353,449		$	22,678	$	156,472		$	22,699		$	509,921			$	45,377
	Total securities available for sale	$	353,449		$	22,678	$	156,472		$	22,699		$	509,921			$	45,377
	The amortized cost, fair value and yield of securities available for sale and securities held to maturity by contractual maturity at December 31, 2014 and 2013, are shown below. The remaining contractual principal maturities do not consider possible prepayments. Remaining expected maturities will differ from contractual maturities because borrowers may have the right to prepay.
		At December 31,
		2014							2013
	(Dollars in thousands)	Amortized Cost			Fair Value		Yield		Amortized Cost			Fair Value				Yield
	Securities available for sale:
	Due in one year or less	$	4		$	4	11.63	%	$	—		$	—			—	%
	Due in 1-5 years	76			76		4.53		138			140				5.24
	Due in 5-10 years	86,806			87,594		1.93		24,328			24,543				2.17
	Due after 10 years	374,744			375,620		2.78		567,910			523,447				2.67
	No stated maturity	—			—		—		1,642			2,934				—
	Total securities available for sale	$	461,630		$	463,294	2.62		$	594,018		$	551,064			2.65
	Securities held to maturity:
	Due in one year or less	$	500		$	500	2	%	$	—		$	—			—	%
	Due in 1-5 years	2,500			2,500		3.08		3,000			3,000				2.9
	Due in 5-10 years	400			400		3		—			—				—
	Due after 10 years	211,054			218,933		2.64		16,912			16,912				3.52
	Total securities held to maturity	$	214,454		$	222,333	2.64		$	19,912		$	19,912			3.43

Loans_and_Leases

Loans and Leases	12 Months Ended
	Dec. 31, 2014
Receivables [Abstract]
Loans and Leases	Loans and Leases
	Loans and leases consisted of the following.
		At December 31,				Percent Change
	(Dollars in thousands)	2014		2013
	Consumer real estate:
	First mortgage lien	$	3,139,152	$	3,766,421	(16.7	)%
	Junior lien	2,543,212		2,572,905		(1.2	)
	Total consumer real estate	5,682,364		6,339,326		(10.4	)
	Commercial:
	Commercial real estate:
	Permanent	2,382,144		2,604,673		(8.5	)
	Construction and development	242,111		139,024		74.2
	Total commercial real estate	2,624,255		2,743,697		(4.4	)
	Commercial business	533,410		404,655		31.8
	Total commercial	3,157,665		3,148,352		0.3
	Leasing and equipment finance	3,745,322		3,428,755		9.2
	Inventory finance	1,877,090		1,664,377		12.8
	Auto finance	1,915,061		1,239,386		54.5
	Other	24,144		26,743		(9.7	)
	Total loans and leases(1)	$	16,401,646	$	15,846,939	3.5
	-1	Loans and leases are reported at historical cost including net direct fees and costs associated with originating and acquiring loans and leases, lease residuals, unearned income and unamortized purchase premiums and discounts. The aggregate amount of these loan and lease adjustments was $43.4 million and $30.3 million at December 31, 2014 and 2013, respectively.
	The consumer real estate junior lien portfolio was comprised of $2.1 billion of home equity lines of credit ("HELOCs") and $424.4 million of amortizing junior lien mortgage loans at December 31, 2014, compared with $2.1 billion and $505.5 million at December 31, 2013, respectively. At December 31, 2014 and 2013, $1.3 billion and $1.1 billion, respectively, of the consumer real estate junior lien HELOCs had a 10-year interest-only draw period and a 20-year amortization repayment period and all were within the 10-year initial draw period and will not convert to amortizing loans until 2021 or later. At December 31, 2014 and 2013, $816.0 million and $969.2 million, respectively, of the consumer real estate junior lien HELOCs were interest-only revolving draw loans with no defined amortization period and original draw periods of 5 to 40 years. As of December 31, 2014, 14.6% of these loans will mature in the next five years.
	In 2014 and 2013, TCF sold $1.3 billion and $0.8 billion, respectively, of consumer auto loans with servicing retained, received cash of $1.4 billion and $0.8 billion, respectively, and recognized net gains of $44.7 million and $29.7 million, respectively. Related to these sales, TCF retained interest-only strips of $17.9 million and $50.7 million in 2014 and 2013, respectively. Total interest-only strips related to sales of auto loans totaled $48.6 million and $64.9 million at December 31, 2014 and 2013, respectively. TCF recorded impairment charges on these interest-only strips of $3.5 million and $5.4 million in 2014 and 2013, respectively, primarily as a result of higher prepayments than originally assumed. Contractual recourse liabilities related to sales of auto loans totaled $0.7 million and $1.1 million at December 31, 2014 and 2013, respectively. No servicing assets or liabilities related to consumer auto loans were recorded within TCF's Consolidated Statements of Financial Condition, as the contractual servicing fees are adequate to compensate TCF for its servicing responsibilities based on the amount demanded by the marketplace. TCF's managed auto loan portfolio, which includes portfolio loans, loans held for sale and loans sold and serviced for others, totaled $3.8 billion and $2.4 billion at December 31, 2014 and 2013, respectively.
	In July 2014, TCF transferred consumer auto loans totaling $256.3 million with servicing retained to a trust in the Company's inaugural securitization transaction, received cash proceeds of $266.7 million and recognized gains of $7.4 million, which qualified for sale accounting and is included in the amounts above. This trust is considered a variable interest entity due to its limited capitalization and special purpose nature, however it is not consolidated as TCF is not the primary beneficiary because the Company does not have a variable interest in the trust.
	In 2014 and 2013, TCF sold $1.4 billion and $0.8 billion, respectively, of consumer real estate loans, received cash of $1.4 billion and $0.8 billion, respectively, and recognized net gains of $34.1 million and $21.7 million, respectively. Related to these sales, TCF retained interest-only strips of $10.8 million and $22.2 million in 2014 and 2013, respectively. Total interest-only strips related to sales of consumer real estate loans totaled $21.2 million and $19.6 million at December 31, 2014 and 2013, respectively. TCF had no impairment charges on these interest-only strips in 2014 and recorded impairment charges of $0.5 million on these interest-only strips in 2013. Contractual recourse liabilities related to sales of consumer real estate loans totaled $0.6 million at both December 31, 2014 and 2013. No servicing assets or liabilities related to consumer real estate loans were recorded within TCF's Consolidated Statements of Financial Condition, as the contractual servicing fees are adequate to compensate TCF for its servicing responsibilities based on the amount demanded by the marketplace. During the fourth quarter of 2014, TCF sold consumer real estate TDR loans totaling $405.9 million, received cash proceeds of $314.0 million and recognized losses of $4.8 million which are included in the amounts above. TCF's managed consumer real estate loan portfolio, which includes portfolio loans, loans held for sale and loans sold and serviced for others, totaled $7.1 billion and $7.0 billion at December 31, 2014 and 2013, respectively.
	From time to time, TCF sells leasing and equipment finance loans and minimum lease payment receivables to third-party financial institutions at fixed rates. In 2014 and 2013, TCF sold $66.9 million and $60.3 million, respectively, of loans and minimum lease payment receivables, received cash of $68.2 million and $62.1 million, respectively, and recognized net gains of $0.4 million and $0.5 million, respectively. Related to these sales, TCF established servicing liabilities of $0.8 million and $1.3 million in 2014 and 2013, respectively. At December 31, 2014 and 2013, TCF had total servicing liabilities related to leasing and equipment finance of $1.5 million and $1.7 million, respectively. At December 31, 2014 and 2013, TCF had lease residuals related to non-recourse sales of $14.2 million and $15.2 million, respectively. TCF's managed leasing and equipment finance loan portfolio, which includes portfolio loans and leases, loans held for sale, operating leases and loans and leases sold and serviced for others, totaled $4.0 billion and $3.7 billion at December 31, 2014 and 2013, respectively.
	There were no material sales of commercial loans in 2014. In 2013, TCF sold $86.5 million of commercial loans and recognized a net gain of $1.6 million, with no servicing liabilities related to these sales.
	TCF's agreements to sell auto and consumer real estate loans typically contain certain representations and warranties regarding the loans sold. These representations and warranties generally relate to, among other things, the ownership of the loan, the validity, priority and perfection of the lien securing the loan, accuracy of information supplied to the buyer, the loan's compliance with the criteria set forth in the agreement, payment delinquency and compliance with applicable laws and regulations. TCF may be required to repurchase loans in the event of an unremedied breach of these representations or warranties. In 2014, 2013 and 2012, losses related to repurchases pursuant to such representations and warranties were immaterial. The majority of such repurchases were of consumer auto loans where TCF typically has contractual agreements with the automobile dealerships that originated the loans requiring the dealers to repurchase such contracts from TCF.
	Future minimum lease payments receivable for direct financing, sales-type leases and operating leases as of December 31, 2014 are as follows:
	(In thousands)
	2015	$	711,813
	2016	529,282
	2017	365,547
	2018	213,241
	2019	105,650
	Thereafter	36,949
	Total	$	1,962,482

Allowance_for_Loan_and_Lease_L

Allowance for Loan and Lease Losses and Credit Quality Information	12 Months Ended
	Dec. 31, 2014
Allowance for Loan and Lease Losses and Credit Quality Information
Allowance for Loan and Lease Losses and Credit Quality Information	Allowance for Loan and Lease Losses and Credit Quality Information
	The following tables provide the allowance for loan and lease losses and other information regarding the allowance for loan and lease losses. TCF's key credit quality indicator is the receivable's payment performance status, defined as accruing or non-accruing.
	(In thousands)	Consumer			Commercial			Leasing and			Inventory			Auto			Other			Total
		Real Estate						Equipment			Finance			Finance
								Finance
	At or For the Year Ended December 31, 2014:
	Balance, beginning of period	$	176,030		$	37,467		$	18,733		$	8,592		$	10,623		$	785		$	252,230
	Charge-offs	(63,126		)	(8,657		)	(7,316		)	(1,653		)	(11,856		)	(8,359		)	(100,967		)
	Recoveries	6,867			2,887			3,705			826			1,491			5,860			21,636
	Net charge-offs	(56,259		)	(5,770		)	(3,611		)	(827		)	(10,365		)	(2,499		)	(79,331		)
	Provision for credit losses	63,973			(259		)	3,324			2,498			23,742			2,459			95,737
	Other(1)	(98,383		)	(71		)	—			(243		)	(5,770		)	—			(104,467		)
	Balance, end of period	$	85,361		$	31,367		$	18,446		$	10,020		$	18,230		$	745		$	164,169
	At or For the Year Ended December 31, 2013:
	Balance, beginning of period	$	182,013		$	51,575		$	21,037		$	7,569		$	4,136		$	798		$	267,128
	Charge-offs	(97,508		)	(28,944		)	(7,277		)	(1,141		)	(5,305		)	(9,115		)	(149,290		)
	Recoveries	8,644			2,770			3,968			373			607			6,518			22,880
	Net charge-offs	(88,864		)	(26,174		)	(3,309		)	(768		)	(4,698		)	(2,597		)	(126,410		)
	Provision for credit losses	87,100			12,515			1,005			1,949			13,215			2,584			118,368
	Other	(4,219		)	(449		)	—			(158		)	(2,030		)	—			(6,856		)
	Balance, end of period	$	176,030		$	37,467		$	18,733		$	8,592		$	10,623		$	785		$	252,230
	-1	Included in Other for consumer real estate is the transfer of $95.3 million, comprised of $77.0 million of previously established allowance for loan and lease losses and an additional $18.3 million of write-downs arising from the transfer to loans held for sale in conjunction with the portfolio sale of consumer real estate TDR loans.
	The following tables provide information regarding the allowance for loan and lease losses and balances by type of allowance methodology.
		At December 31, 2014
	(In thousands)	Consumer			Commercial			Leasing and			Inventory			Auto			Other			Total
		Real Estate						Equipment			Finance			Finance
								Finance
	Allowance for loan and lease losses:
	Collectively evaluated for impairment	$	57,167		$	27,594		$	16,310		$	9,627		$	17,046		$	741		$	128,485
	Individually evaluated for impairment	28,194			3,773			2,136			393			1,184			4			35,684
	Total	$	85,361		$	31,367		$	18,446		$	10,020		$	18,230		$	745		$	164,169
	Loans and leases outstanding:
	Collectively evaluated for impairment	$	5,462,005		$	3,038,378		$	3,731,420		$	1,874,481		$	1,911,267		$	24,055		$	16,041,606
	Individually evaluated for impairment	220,359			119,287			13,763			2,609			3,676			89			359,783
	Loans acquired with deteriorated credit quality	—			—			139			—			118			—			257
	Total	$	5,682,364		$	3,157,665		$	3,745,322		$	1,877,090		$	1,915,061		$	24,144		$	16,401,646
		At December 31, 2013
	(In thousands)	Consumer			Commercial			Leasing and			Inventory			Auto			Other			Total
		Real Estate						Equipment			Finance			Finance
								Finance
	Allowance for loan and lease losses:
	Collectively evaluated for impairment	$	54,449		$	28,994		$	17,093		$	8,308		$	10,528		$	781		$	120,153
	Individually evaluated for impairment	121,581			8,473			1,640			284			95			4			132,077
	Total	$	176,030		$	37,467		$	18,733		$	8,592		$	10,623		$	785		$	252,230
	Loans and leases outstanding:
	Collectively evaluated for impairment	$	5,673,518		$	2,971,308		$	3,412,769		$	1,657,636		$	1,238,556		$	26,649		$	14,980,436
	Individually evaluated for impairment	665,808			177,044			15,139			6,741			470			94			865,296
	Loans acquired with deteriorated credit quality	—			—			847			—			360			—			1,207
	Total	$	6,339,326		$	3,148,352		$	3,428,755		$	1,664,377		$	1,239,386		$	26,743		$	15,846,939
	Accruing and Non-accrual Loans and Leases  The following tables set forth information regarding TCF's accruing and non-accrual loans and leases. Non-accrual loans and leases are those which management believes have a higher risk of loss. Delinquent balances are determined based on the contractual terms of the loan or lease.
		At December 31, 2014
	(In thousands)	Current-59 Days			60-89 Days			90 Days or More			Total			Non-accrual			Total
		Delinquent and			Delinquent			Delinquent and			Accruing
		Accruing			and Accruing			Accruing
	Consumer real estate:
	First mortgage lien	$	2,987,992		$	13,176		$	194		$	3,001,362		$	137,790		$	3,139,152
	Junior lien	2,505,640			2,091			—			2,507,731			35,481			2,543,212
	Total consumer real estate	5,493,632			15,267			194			5,509,093			173,271			5,682,364
	Commercial:
	Commercial real estate	2,599,701			—			—			2,599,701			24,554			2,624,255
	Commercial business	532,929			—			—			532,929			481			533,410
	Total commercial	3,132,630			—			—			3,132,630			25,035			3,157,665
	Leasing and equipment finance	3,728,115			2,242			307			3,730,664			12,670			3,743,334
	Inventory finance	1,874,933			49			26			1,875,008			2,082			1,877,090
Auto finance	1,907,005			2,785			1,478			1,911,268			3,676			1,914,944
Other	24,144			—			—			24,144			—			24,144
Subtotal	16,160,459			20,343			2,005			16,182,807			216,734			16,399,541
Portfolios acquired with deteriorated credit quality	2,017			83			5			2,105			—			2,105
Total	$	16,162,476		$	20,426		$	2,010		$	16,184,912		$	216,734		$	16,401,646
	At December 31, 2013
(In thousands)	Current-59 Days			60-89 Days			90 Days or More			Total			Non-accrual			Total
	Delinquent and			Delinquent			Delinquent and			Accruing
	Accruing			and Accruing			Accruing
Consumer real estate:
First mortgage lien	$	3,564,716		$	19,815		$	1,079		$	3,585,610		$	180,811		$	3,766,421
Junior lien	2,531,151			3,532			—			2,534,683			38,222			2,572,905
Total consumer real estate	6,095,867			23,347			1,079			6,120,293			219,033			6,339,326
Commercial:
Commercial real estate	2,706,633			886			—			2,707,519			36,178			2,743,697
Commercial business	399,750			190			354			400,294			4,361			404,655
Total commercial	3,106,383			1,076			354			3,107,813			40,539			3,148,352
Leasing and equipment finance	3,404,346			2,226			613			3,407,185			14,041			3,421,226
Inventory finance	1,661,798			29			21			1,661,848			2,529			1,664,377
Auto finance	1,236,678			1,105			773			1,238,556			470			1,239,026
Other	26,323			9			1			26,333			410			26,743
Subtotal	15,531,395			27,792			2,841			15,562,028			277,022			15,839,050
Portfolios acquired with deteriorated credit quality	7,870			14			5			7,889			—			7,889
Total	$	15,539,265		$	27,806		$	2,846		$	15,569,917		$	277,022		$	15,846,939
The following table provides interest income recognized on loans and leases in non-accrual status and contractual interest that would have been recorded had the loans and leases performed in accordance with their original contractual terms.
	Year Ended December 31,
(In thousands)	2014			2013			2012
Contractual interest due on non-accrual loans and leases	$	26,584		$	33,046		$	39,232
Interest income recognized on non-accrual loans and leases	9,359			12,149			9,401
Foregone interest income	$	17,225		$	20,897		$	29,831
The following table provides information regarding consumer real estate loans to customers currently involved in ongoing Chapter 7 or Chapter 13 bankruptcy proceedings which have not yet been discharged.
	At December 31,
(In thousands)	2014			2013
Consumer real estate loans to customers in bankruptcy:
0-59 days delinquent and accruing	$	47,731		$	65,321
60+ days delinquent and accruing	247			682
Non-accrual	12,284			13,475
Total consumer real estate loans to customers in bankruptcy	$	60,262		$	79,478
For the years ended December 31, 2014 and 2013, interest income would have been reduced by approximately $0.4 million and $0.9 million, respectively, had the accrual of interest income on the above consumer loans been discontinued upon notification of bankruptcy.
Loan Modifications for Borrowers with Financial Difficulties  Included within loans and leases in the previous tables are certain loans that have been modified in order to maximize collection of loan balances. If, for economic or legal reasons related to the customer's financial difficulties, TCF grants a concession, the modified loan is classified as a TDR. TDR loans consist primarily of consumer real estate and commercial loans.
Total TDR loans at December 31, 2014 and 2013 were $298.5 million and $796.5 million, respectively, of which $193.8 million and $632.8 million were accruing at December 31, 2014 and 2013, respectively. TCF held consumer real estate TDR loans of $199.6 million and $641.1 million at December 31, 2014 and 2013, respectively, of which $111.9 million and $506.6 million were accruing at December 31, 2014 and 2013, respectively. TCF also held $91.6 million and $147.1 million of commercial TDR loans at December 31, 2014 and 2013, respectively, of which $80.4 million and $120.9 million were accruing at December 31, 2014 and 2013, respectively. TDR loans for the remaining classes of finance receivables were not material at December 31, 2014 or 2013. TCF sold $405.9 million of consumer real estate TDR loans in a portfolio sale during December 2014.
The amount of unfunded commitments to consumer real estate and commercial loans classified as TDRs was $3.9 million and $6.1 million at December 31, 2014 and 2013, respectively. At December 31, 2014 and 2013, no additional funds were committed to leasing and equipment finance, inventory finance or auto finance loans classified as TDRs.
When a loan is modified as a TDR, principal balances are generally not forgiven. Loan modifications to troubled borrowers are not reported as TDR loans in the calendar year after modification if the loans were modified at an interest rate equal to the yields of new loan originations with comparable risk and the loans are performing based on the terms of the restructured agreements. All loans classified as TDR loans are considered to be impaired. In 2014 and 2013, $12.8 million and $17.1 million, respectively, of commercial loans were removed from TDR status as they were restructured at market terms and are performing.
The financial effects of TDR loans represent the difference between interest income recognized on accruing TDR loans and the contractual interest that would have been recorded under the original contractual terms, or foregone interest income. For the year ended December 31, 2014, foregone interest income for consumer real estate first mortgage lien accruing TDR loans and consumer real estate junior lien accruing TDR loans was $16.7 million and $1.2 million, respectively. The average yield for the same period on consumer real estate accruing TDR loans was 3.3%, which compares to the original contractual average rate of 6.8%. For the year ended December 31, 2013, foregone interest income for consumer real estate first mortgage lien accruing TDR loans and consumer real estate junior lien accruing TDR loans was $17.6 million and $1.2 million, respectively. The average yield for the same period on consumer real estate accruing TDR loans was 3.3%, which compares to the original contractual average rate of 6.9%. For the year ended December 31, 2012, foregone interest income for consumer real estate first mortgage lien accruing TDR loans and consumer real estate junior lien accruing TDR loans was $13.9 million and $0.9 million, respectively. The average yield for the same period on consumer real estate accruing TDR loans was 3.7%, which compares to the original contractual average rate of 6.9%. The foregone interest income for the remaining classes of finance receivables was not material for the years ended December 31, 2014, 2013 and 2012.
The table below summarizes TDR loans that defaulted during the years ended December 31, 2014 and 2013, which were modified during the respective reporting period or within one year of the beginning of the respective reporting period. TCF considers a loan to have defaulted when it becomes 90 or more days delinquent under the modified terms, has been transferred to non-accrual status subsequent to the modification or has been transferred to other real estate owned or repossessed and returned assets.
	Loan Balance(1)
	Year Ended December 31,
(Dollars in thousands)	2014			2013
Consumer real estate:
First mortgage lien	$	1,969		$	12,510
Junior lien	1,364			2,479
Total consumer real estate	3,333			14,989
Commercial:
Commercial real estate	3,895			5,561
Commercial business	127			—
Total commercial	4,022			5,561
Leasing and equipment finance	—			268
Auto finance	392			59
Other	—			1
Defaulted TDR loans modified during the applicable period	$	7,747		$	20,878
Total loans modified in the applicable period	$	177,674		$	374,761
Defaulted modified TDR loans as a percent of total loans modified in the applicable period	4.4		%	5.6		%
-1	The loan balances presented are not materially different than the pre-modification loan balances as TCF's loan modifications generally do not forgive principal amounts.
Consumer real estate TDR loans are evaluated separately in TCF's allowance methodology. Impairment is generally based upon the present value of the expected future cash flows or the fair value of the collateral less selling expenses for collateral dependent loans. The allowance on accruing consumer real estate TDR loans was $20.4 million, or 18.2% of the outstanding balance, at December 31, 2014, and $103.3 million, or 20.4% of the outstanding balance, at December 31, 2013. In determining impairment for consumer real estate accruing TDR loans, TCF utilized assumed remaining re-default rates ranging from 4% to 22% in 2014 and 6% to 25% in 2013, depending on modification type and actual experience. At December 31, 2014, 2.4% of accruing consumer real estate TDR loans were more than 60-days delinquent, compared with 1.4% at December 31, 2013.
Consumer real estate TDR loans generally remain on accruing status following modification if they are less than 90 days past due and payment in full under the modified terms of the loan is expected based on a current credit evaluation and historical payment performance. Of the non-accrual TDR balance at December 31, 2014, $50.0 million, or 57.0%, were loans discharged in Chapter 7 bankruptcy that were not reaffirmed, of which 68.4% were current. Of the non-accrual TDR balance at December 31, 2013, $81.5 million, or 60.6%, were loans discharged in Chapter 7 bankruptcy that were not reaffirmed, of which 71.8% were current. All eligible loans are re-aged to current delinquency status upon modification.
Commercial TDR loans are individually evaluated for impairment based upon the present value of the expected future cash flows, or for collateral dependent loans, at the fair value of collateral less selling expense. The allowance on accruing commercial TDR loans was $1.4 million, or 1.7% of the outstanding balance, at December 31, 2014, and $6.3 million, or 5.2% of the outstanding balance, at December 31, 2013. No accruing commercial TDR loans were 60 days or more delinquent at December 31, 2014, compared with one commercial TDR loan with $0.9 million outstanding at December 31, 2013.
Impaired Loans  TCF considers impaired loans to include non-accrual commercial loans, non-accrual equipment finance loans and non-accrual inventory finance loans, as well as all TDR loans. Non-accrual impaired loans, including non-accrual TDR loans, are included in non-accrual loans and leases within the previous tables. Accruing TDR loans have been disclosed by delinquency status within the previous tables of accruing and non-accrual loans and leases. In the following tables, the loan balance of impaired loans represents the amount recorded within loans and leases on the Consolidated Statements of Financial Condition, whereas the unpaid contractual balance represents the balances legally owed by the borrowers.
The following table summarizes impaired loans.
	At December 31,
	2014									2013
(In thousands)	Unpaid			Loan			Related			Unpaid Contractual Balance			Loan			Related Allowance Recorded
	Contractual			Balance			Allowance						Balance
	Balance						Recorded
Impaired loans with an allowance recorded:
Consumer real estate:
First mortgage lien	$	114,526		$	101,668		$	18,140		$	553,736		$	521,248		$	107,841
Junior lien	65,413			55,405			9,427			85,309			72,548			12,989
Total consumer real estate	179,939			157,073			27,567			639,045			593,796			120,830
Commercial:
Commercial real estate	58,157			54,412			3,772			84,851			71,785			7,594
Commercial business	18			18			1			9,917			4,380			880
Total commercial	58,175			54,430			3,773			94,768			76,165			8,474
Leasing and equipment finance	8,257			8,257			1,457			8,238			8,238			717
Inventory finance	1,754			1,758			393			6,741			6,741			284
Auto finance	3,074			2,928			1,184			373			308			95
Other	92			89			4			97			94			4
Total impaired loans with an allowance recorded	251,291			224,535			34,378			749,262			685,342			130,404
Impaired loans without an allowance recorded:
Consumer real estate:
First mortgage lien	53,606			35,147			—			59,233			43,025			—
Junior lien	33,796			7,398			—			26,710			4,306			—
Total consumer real estate	87,402			42,545			—			85,943			47,331			—
Commercial:
Commercial real estate	57,809			50,500			—			102,523			79,833			—
Commercial business	482			480			—			5,410			5,412			—
Total commercial	58,291			50,980			—			107,933			85,245			—
Inventory finance	848			851			—			—			—			—
Auto finance	1,484			748			—			317			162			—
Total impaired loans without an allowance recorded	148,025			95,124			—			194,193			132,738			—
Total impaired loans	$	399,316		$	319,659		$	34,378		$	943,455		$	818,080		$	130,404
The average loan balance of impaired loans and interest income recognized on impaired loans during the years ended December 31, 2014 and 2013 are included within the table below.
	Year Ended December 31,
	2014						2013
(In thousands)	Average Loan Balance			Interest Income Recognized			Average Loan Balance			Interest Income Recognized
Impaired loans with an allowance recorded:
Consumer real estate:
First mortgage lien	$	311,458		$	14,715		$	481,292		$	17,263
Junior lien	63,977			3,492			57,692			3,762
Total consumer real estate	375,435			18,207			538,984			21,025
Commercial:
Commercial real estate	63,099			2,349			99,177			3,193
Commercial business	2,199			—			10,060			70
Total commercial	65,298			2,349			109,237			3,263
Leasing and equipment finance	8,247			58			7,954			174
Inventory finance	4,249			97			4,114			158
Auto finance	1,617			—			154			2
Other	92			7			66			6
Total impaired loans with an allowance recorded	454,938			20,718			660,509			24,628
Impaired loans without an allowance recorded:
Consumer real estate:
First mortgage lien	39,086			2,321			92,268			2,305
Junior lien	5,852			1,285			15,236			1,682
Total consumer real estate	44,938			3,606			107,504			3,987
Commercial:
Commercial real estate	65,167			2,973			101,921			3,165
Commercial business	2,946			94			5,674			215
Total commercial	68,113			3,067			107,595			3,380
Inventory finance	426			126			—			—
Auto finance	455			—			132			—
Total impaired loans without an allowance recorded	113,932			6,799			215,231			7,367
Total impaired loans	$	568,870		$	27,517		$	875,740		$	31,995

Premises_and_Equipment

Premises and Equipment	12 Months Ended
	Dec. 31, 2014
Property, Plant and Equipment [Abstract]
Premises and Equipment	Premises and Equipment
	Premises and equipment consisted of the following.
		At December 31,
	(In thousands)	2014		2013
	Land	$	152,418	$	154,136
	Office buildings	276,943		277,085
	Leasehold improvements	53,954		54,069
	Furniture and equipment	312,628		294,387
	Subtotal	795,943		779,677
	Less: Accumulated depreciation and amortization	359,582		342,075
	Total	$	436,361	$	437,602
	TCF leases certain premises and equipment under operating leases. Net lease expense including utilities and other operating expenses was $34.0 million, $35.4 million and $35.5 million in 2014, 2013 and 2012, respectively.
	At December 31, 2014, the total future minimum rental payments for operating leases of premises and equipment are as follows.
	(In thousands)
	2015	$	26,894
	2016	29,592
	2017	28,201
	2018	26,355
	2019	15,199
	Thereafter	67,030
	Total	$	193,271

Goodwill_and_Other_Intangible_

Goodwill and Other Intangible Assets	12 Months Ended
	Dec. 31, 2014
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Other Intangible Assets	Goodwill and Other Intangible Assets
	Goodwill and other intangible assets consisted of the following.
		At December 31,
		2014						2013
	(In thousands)	Gross		Accumulated		Net		Gross		Accumulated		Net
		Amount		Amortization		Amount		Amount		Amortization		Amount
	Amortizable intangible assets:
	Deposit base intangibles	$	3,049	$	1,502	$	1,547	$	3,049	$	1,105	$	1,944
	Customer base intangibles	2,730		1,377		1,353		2,730		996		1,734
	Non-compete agreement	4,590		2,849		1,741		4,590		1,942		2,648
	Tradename	300		300		—		300		300		—
	Total	$	10,669	$	6,028	$	4,641	$	10,669	$	4,343	$	6,326
	Unamortizable intangible assets:
	Goodwill related to funding segment	$	141,245			$	141,245	$	141,245			$	141,245
	Goodwill related to lending segment	84,395				84,395		84,395				84,395
	Total	$	225,640			$	225,640	$	225,640			$	225,640
	Amortization expense for intangible assets of $1.7 million, $2.3 million and $1.5 million were recognized in 2014, 2013 and 2012, respectively. Amortization expense for intangible assets is estimated to be $1.6 million for 2015, $1.4 million for 2016, $0.5 million for 2017, $0.4 million for 2018 and $0.3 million for 2019. There was no impairment of goodwill or the intangible assets in 2014, 2013 or 2012.

Deposits

Deposits	12 Months Ended
	Dec. 31, 2014
Deposits [Abstract]
Deposits	Deposits
	Deposits consisted of the following.
		At December 31,
		2014								2013
	(Dollars in thousands)	Weighted-Average Rate		Amount			% of			Weighted-Average Rate		Amount		% of
							Total							Total
	Checking:
	Non-interest bearing	—	%	$	2,832,526		18.3	%		—	%	$	2,642,600	18.3	%
	Interest bearing	0.04		2,362,717			15.3			0.06		2,337,851		16.2
	Total checking	0.02		5,195,243			33.6			0.03		4,980,451		34.5
	Savings	0.15		5,212,320			33.7			0.2		6,194,003		42.9
	Money market	0.54		1,993,130			13			0.29		831,910		5.8
	Total checking, savings and money market	0.13		12,400,693			80.3			0.14		12,006,364		83.2
	Certificates of deposit	0.78		3,049,189			19.7			0.86		2,426,412		16.8
	Total deposits	0.26		$	15,449,882		100	%		0.26		$	14,432,776	100	%
	Certificates of deposit had the following remaining maturities at December 31, 2014.
	(In thousands)	Denominations			Denominations			Total
		$100 Thousand or			Less Than
		Greater			$100 Thousand
	Maturity:
	0-3 months	$	250,200		$	348,379		$	598,579
	4-6 months	150,195			244,631			394,826
	7-12 months	345,161			491,403			836,564
	13-24 months	505,991			587,088			1,093,079
	Over 24 months	75,609			50,532			126,141
	Total	$	1,327,156		$	1,722,033		$	3,049,189

Shortterm_Borrowings

Short-term Borrowings	12 Months Ended
	Dec. 31, 2014
Debt Disclosure [Abstract]
Short-term Borrowings	Short-term Borrowings
	Selected information for short-term borrowings (borrowings with an original maturity of less than one year) consisted of the following.
		At December 31,
		2014				2013
	(Dollars in thousands)	Amount		Rate		Amount		Rate
	Period end balance:
	Securities sold under repurchase agreements	$	4,425	0.1	%	$	4,918	0.1	%
	Total	$	4,425	0.1		$	4,918	0.1
	Average daily balances for the period ended:
	Federal Home Loan Bank advances	$	74,385	0.26	%	$	14	0.34	%
	Federal funds purchased	375		0.4		660		0.34
	Securities sold under repurchase agreements	5,956		0.18		5,713		0.18
	Line of Credit - TCF Commercial Finance Canada, Inc.	2,957		1.88		1,298		2.57
	Total	$	83,673	0.31		$	7,685	0.6
	Maximum month-end balances for the period ended:
	Federal Home Loan Bank advances	$	250,000	N.A.		$	—	N.A.
	Securities sold under repurchase agreements	4,425		N.A.		7,071		N.A.
	Line of Credit - TCF Commercial Finance Canada, Inc.	11,751		N.A.		9,587		N.A.
	N.A. Not Applicable.
	At December 31, 2014, the securities sold under short-term repurchase agreements were related to TCF Bank's Repurchase Investment Sweep Agreement product and were collateralized by mortgage-backed securities having a fair value of $6.8 million.

Longterm_Borrowings

Long-term Borrowings	12 Months Ended
	Dec. 31, 2014
Debt Disclosure [Abstract]
Long-term Borrowings	Long-term Borrowings
	Long-term borrowings consisted of the following.
			At December 31,
			2014				2013
	(Dollars in thousands)	Stated	Amount		Weighted-		Amount		Weighted-
		Maturity			Average Rate				Average Rate
	Federal Home Loan Bank advances	2014	$	—	—	%	$	398,000	0.37	%
		2015	125,000		0.38		200,000		0.33
		2016	547,000		0.75		497,000		0.76
		2017	275,000		0.25		75,000		0.21
	Subtotal		947,000		0.56		1,170,000		0.52
	Subordinated bank notes	2015	—		—		50,000		1.83
		2016	74,930		5.59		74,868		5.59
		2022	109,194		6.37		109,113		6.37
	Subtotal		184,124		6.05		233,981		5.15
	Discounted lease rentals	2014	—		—		26,275		4.06
		2015	32,904		3.84		18,866		3.96
		2016	27,539		3.83		13,319		3.92
		2017	20,580		3.82		8,281		3.69
		2018	9,032		3.92		1,689		3.45
		2019	2,589		4.23		76		3.31
		2020	160		4.57		—		—
		2021	83		4.57		—		—
	Subtotal		92,887		3.85		68,506		3.94
	Other long-term	2014	—		—		2,718		1.36
		2015	2,670		1.36		2,669		1.36
		2016	2,642		1.36		2,705		1.36
		2017	2,742		1.36		2,746		1.36
	Subtotal		8,054		1.36		10,838		1.36
	Total long-term borrowings		$	1,232,065	1.63		$	1,483,325	1.41
	At December 31, 2014, TCF Bank had pledged loans secured by residential real estate, commercial real estate and FHLB stock with an aggregate carrying value of $5.2 billion as collateral for FHLB advances. At December 31, 2014, $375.0 million of FHLB advances outstanding were prepayable monthly at TCF's option.
	On March 17, 2014, TCF Bank redeemed at par $50.0 million of subordinated notes due 2015, since the notes no longer qualified for treatment as Tier 2 or supplementary capital prior to redemption.
	The $74.9 million of subordinated notes due 2016 have a fixed-rate coupon of 5.5% per annum until maturity. The $109.2 million of subordinated notes due 2022 have a fixed-rate coupon of 6.25% per annum until maturity. At December 31, 2014, all of the subordinated notes qualify as Tier 2 or supplementary capital for regulatory purposes, subject to certain regulatory limitations.

Income_Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes
	The following table summarizes applicable income taxes in the Consolidated Statements of Income.
	(In thousands)	Current				Deferred				Total
	Year ended December 31, 2014:
	Federal	$	55,062			$	26,308			$	81,370
	State	2,087				11,147				13,234
	Foreign	5,185				(23		)		5,162
	Total	$	62,334			$	37,432			$	99,766
	Year ended December 31, 2013:
	Federal	$	(38,206	)		$	107,630			$	69,424
	State	7,686				3,941				11,627
	Foreign	3,939				(645		)		3,294
	Total	$	(26,581	)		$	110,926			$	84,345
	Year ended December 31, 2012:
	Federal	$	6,646			$	(129,082	)		$	(122,436	)
	State	7,994				(18,416		)		(10,422		)
	Total	$	14,640			$	(147,498	)		$	(132,858	)
	TCF's effective income tax rate differed from the statutory federal income tax rate of 35.0% as a result of the following.
		Year Ended December 31,
		2014			2013			2012
	Federal income tax rate	35	%		35	%		35	%
	Increase (decrease) resulting from:
	State income tax, net of federal income tax	3.06			3.11			1.99
	Non-controlling interest tax effect	(0.92	)		(1.01	)		0.64
	Tax exempt income	(0.76	)		(0.86	)		0.55
	Foreign tax effects	(0.58	)		(1.13	)		—
	Deferred tax adjustments	(0.33	)		(0.30	)		1.4
	Civil money penalty	—			—			(1.03	)
	Other, net	(0.01	)		(0.11	)		0.58
	Effective income tax rate	35.46	%		34.7	%		39.13	%
	Beginning in the second quarter of 2013, TCF considered its undistributed foreign earnings to be reinvested indefinitely. As a result, TCF recorded a $1.2 million benefit in 2013 to eliminate U.S. deferred taxes on its undistributed foreign earnings. This assertion is based on management's determination that cash held in TCF's foreign jurisdictions is not needed to fund its U.S. operations and that it either has reinvested or has intentions to reinvest these earnings. While management currently intends to indefinitely reinvest all of TCF's foreign earnings, should circumstances or tax laws change, TCF may need to record additional income tax expense in the period in which such determination or tax law change occurs. As of December 31, 2014 and 2013, TCF has not provided U.S. deferred taxes on $48.1 million and $33.5 million, respectively, of its undistributed foreign earnings. If these undistributed earnings were repatriated to the U.S. or otherwise became subject to U.S. taxation, the potential deferred tax liability would be approximately $4.0 million and $2.7 million, as of December 31, 2014 and 2013, respectively, assuming full utilization of related foreign tax credits.
	A reconciliation of the changes in unrecognized tax benefits is as follows.
		At or For the Year Ended December 31,
	(In thousands)	2014				2013				2012
	Balance, beginning of period	$	4,704			$	4,230			$	2,377
	Increases for tax positions related to the current year	468				394				449
	Increases for tax positions related to prior years	8				362				1,781
	Decreases for tax positions related to prior years	(350		)		(67		)		—
	Settlements with taxing authorities	—				(39		)		(70		)
	Decreases related to lapses of applicable statutes of limitation	(181		)		(176		)		(307		)
	Balance, end of period	$	4,649			$	4,704			$	4,230
	The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate was $1.5 million and $1.2 million at December 31, 2014 and 2013, respectively. TCF recognizes interest and penalties related to unrecognized tax benefits, where applicable, in income tax expense. TCF recognized approximately $71 thousand, $110 thousand and $77 thousand in interest and penalties during 2014, 2013 and 2012, respectively. Interest and penalties of approximately $498 thousand and $427 thousand were accrued at December 31, 2014 and 2013, respectively.
	TCF's federal income tax returns are open and subject to examination for 2012 and later tax return years. TCF's various state income tax returns are generally open for the 2010 and later tax return years based on individual state statutes of limitation. TCF's various foreign income tax returns are open and subject to examination for 2010 and later tax return years. Changes in the amount of unrecognized tax benefits within the next twelve months from normal expirations of statutes of limitation are not expected to be material.
	The significant components of the Company's deferred tax assets and deferred tax liabilities were as follows.
		At December 31,
	(In thousands)	2014				2013
	Deferred tax assets:
	Allowance for loan and lease losses	$	63,862			$	62,464
	Stock compensation and deferred compensation plans	34,850				29,576
	Net operating losses and credit carryforwards	11,649				48,692
	Valuation allowance	(5,669		)		(8,745		)
	Non-accrual interest	9,333				1,911
	Securities available for sale	5,397				16,301
	Accrued expense	4,892				5,203
	Other	2,721				6,676
	Total deferred tax assets	127,035				162,078
	Deferred tax liabilities:
	Lease financing	299,621				284,767
	Premises and equipment	19,114				19,289
	Loan fees and discounts	14,921				17,287
	Prepaid expenses	12,479				10,526
	Goodwill and other intangibles	4,139				4,694
	Other	8,106				7,361
	Total deferred tax liabilities	358,380				343,924
Net deferred tax liabilities	$	231,345			$	181,846
The net operating losses and credit carryforwards at December 31, 2014 consist of state net operating losses of $6.0 million that expire in years 2015 through 2034. The valuation allowance at December 31, 2014 and 2013 principally applies to net operating losses and tax credit carryforwards that, in the opinion of management, are more likely than not to expire un-utilized. However, to the extent that tax benefits related to these carryforwards are realized in the future, the reduction in the valuation allowance will reduce income tax expense.

Equity

Equity	12 Months Ended
	Dec. 31, 2014
Equity [Abstract]
Equity	Equity
	Restricted Retained Earnings Retained earnings at TCF Bank, at December 31, 2014, included approximately $134.4 million for which no provision for federal income taxes has been made. This amount represents earnings legally appropriated to thrift bad debt reserves and deducted for federal income tax purposes in prior years and is generally not available for payment of cash dividends or other distributions to stockholders. Future payments or distributions of these appropriated earnings could invoke a tax liability for TCF based on the amount of the distributions and the tax rates in effect at that time.
	Treasury Stock and Other Treasury stock and other consisted of the following.
		At December 31,
	(In thousands)	2014			2013
	Treasury stock, at cost	$	(1,102	)	$	(1,102	)
	Shares held in trust for deferred compensation plans, at cost	(48,298		)	(41,096		)
	Total	$	(49,400	)	$	(42,198	)
	Repurchases No repurchases of common stock were made in 2014, 2013 or 2012. At December 31, 2014, TCF had 5.4 million shares remaining in its stock repurchase programs authorized by TCF's Board of Directors. Prior consultation with the Federal Reserve is required by regulation before TCF could repurchase any shares of its common stock.
	Depositary Shares Representing 7.50% Series A Non-Cumulative Perpetual Preferred Stock On June 25, 2012, TCF completed the public offering of depositary shares, each representing a 1/1000th interest in a share of Series A Non-Cumulative Perpetual Preferred Stock, par value $0.01 per share (the "Series A Preferred Stock"). In connection with the offering, TCF issued 6,900,000 depositary shares at a public offering price of $25 per depositary share. Dividends are payable on the Series A Preferred Stock if, as and when declared by TCF's Board of Directors on a non-cumulative basis on March 1, June 1, September 1 and December 1 of each year at a per annum rate of 7.5%. Net proceeds of the offering to TCF, after deducting underwriting discounts and commissions and estimated offering expenses of $5.8 million, were $166.7 million. TCF paid $12.9 million in cash dividends to holders of Series A Preferred Stock during 2014 and 2013, respectively.
	6.45% Series B Non-Cumulative Perpetual Preferred Stock On December 19, 2012, TCF completed the public offering of 4,000,000 shares of 6.45% Series B Non-Cumulative Perpetual Preferred Stock par value $0.01 per share (the "Series B Preferred Stock"). Net proceeds of the offering to TCF, after deducting underwriting discounts, commissions and estimated offering costs of $3.5 million, were $96.5 million. Dividends are payable on the Series B Preferred Stock if, as and when declared by TCF's Board of Directors on a non-cumulative basis on March 1, June 1, September 1 and December 1 of each year, commencing on March 1, 2013, at a per annum rate of 6.45%. TCF paid $6.5 million and $6.1 million in cash dividends to holders of Series B Preferred stock during 2014 and 2013, respectively.
	Shares Held in Trust for Deferred Compensation Plans
	Executive, Senior Officer, Winthrop and Directors Deferred Compensation Plans TCF has maintained the deferred compensation plans listed above, which previously allowed eligible executives, senior officers, directors and certain other employees and non-employee directors to defer a portion of certain payments, and, in some cases, grants of restricted stock. In October 2008, TCF terminated the employee plans and only the Director plan remains active, which allows non-employee directors to defer up to 100% of their director fees and restricted stock awards. The amounts deferred under these plans were invested in TCF common stock, other publicly traded stocks, bonds or mutual funds. At December 31, 2014, the fair value of the assets in these plans totaled $13.8 million and included $8.6 million invested in TCF common stock, compared with a total fair value of $15.1 million, including $9.4 million invested in TCF common stock at December 31, 2013.
	TCF Employees Deferred Stock Compensation Plan In 2011, TCF implemented the TCF Employees Deferred Stock Compensation Plan. This plan is comprised of restricted stock awards issued to certain executives. The assets of this plan are solely held in TCF common stock with a fair value totaling $33.2 million and $30.2 million at December 31, 2014 and 2013, respectively.
	TCF Employees Stock Purchase Plan - Supplemental Plan TCF also maintains the TCF Employees Stock Purchase Plan - Supplemental Plan, a non-qualified plan, to which certain employees can contribute up to 50% of their salary and bonus. TCF matching contributions to this plan totaled $1.5 million and $0.8 million in 2014 and 2013, respectively. The Company made no other contributions to this plan, other than payment of administrative expenses. The amounts deferred under the above plan were invested in TCF common stock or mutual funds. At December 31, 2014, the fair value of the assets in the plan totaled $31.8 million and included $18.3 million invested in TCF common stock, compared with a total fair value of $27.8 million, including $16.4 million invested in TCF common stock at December 31, 2013.
	The cost of TCF common stock held by TCF's deferred compensation plans is reported separately in a manner similar to treasury stock (that is, changes in fair value are not recognized) with a corresponding deferred compensation obligation reflected in additional paid-in capital.
	Warrants At December 31, 2014, TCF had 3,199,988 warrants outstanding with an exercise price of $16.93 per share, which expire on November 14, 2018. Upon the completion of the U.S. Treasury's secondary public offering of the warrants issued under the Capital Purchase Program ("CPP") in December 2009, the warrants became publicly traded on the New York Stock Exchange under the symbol "TCBWS," As a result, TCF has no further obligations to the Federal Government in connection with the CPP.
	Joint Venture TCF has a joint venture with The Toro Company ("Toro") called Red Iron Acceptance, LLC ("Red Iron"). Red Iron provides U.S. distributors and dealers and select Canadian distributors of the Toro® and Exmark® branded products with sources of financing. TCF and Toro maintain a 55% and 45% ownership interest, respectively, in Red Iron. As TCF has a controlling financial interest in Red Iron, its financial results are consolidated in TCF's financial statements. Toro's interest is reported as a non-controlling interest within equity and qualifies as Tier 1 regulatory capital.

Regulatory_Capital_Requirement

Regulatory Capital Requirements	12 Months Ended
	Dec. 31, 2014
Regulatory Capital Requirements [Abstract]
Regulatory Capital Requirements	Regulatory Capital Requirements
	TCF and TCF Bank are subject to various regulatory capital requirements administered by the federal banking agencies. Failure to meet minimum capital requirements can initiate certain mandatory, and possible additional discretionary, actions by the federal banking agencies that could have a material adverse effect on TCF. In general, TCF Bank may not declare or pay a dividend to TCF Financial in excess of 100% of its net retained profits for the current year combined with its net retained profits for the preceding two calendar years, which was $83.7 million at December 31, 2014, without prior approval of the Office of the Comptroller of the Currency ("OCC"). TCF Bank's ability to make capital distributions in the future may require regulatory approval and may be restricted by its regulatory authorities. TCF Bank's ability to make any such distributions will also depend on its earnings and ability to meet minimum regulatory capital requirements in effect during future periods. These capital adequacy standards may be higher in the future than existing minimum regulatory capital requirements.
	The following table presents regulatory capital information for TCF and TCF Bank.
		Actual				Minimum				Well-Capitalized
						Capital Requirement(1)				Capital Requirement(1)
	(Dollars in thousands)	Amount		Ratio		Amount		Ratio		Amount		Ratio
	At December 31, 2014:
	Tier 1 leverage capital:(2)
	TCF	$	1,919,887	10.07	%	$	762,711	4	%	N.A.		N.A.
	TCF Bank	1,836,019		9.63		762,746		4		$	953,432	5	%
	Tier 1 risk-based capital:
	TCF	1,919,887		11.76		652,857		4		979,286		6
	TCF Bank	1,836,019		11.25		652,785		4		979,177		6
	Total risk-based capital:
	TCF	2,209,999		13.54		1,305,714		8		1,632,143		10
	TCF Bank	2,126,131		13.03		1,305,569		8		1,631,961		10
	At December 31, 2013:
	Tier 1 leverage capital:(2)
	TCF	$	1,763,682	9.71	%	$	726,242	4	%	N.A.		N.A.
	TCF Bank	1,675,082		9.23		725,895		4		$	907,368	5	%
	Tier 1 risk-based capital:
	TCF	1,763,682		11.41		618,228		4		927,342		6
	TCF Bank	1,675,082		10.84		618,033		4		927,049		6
	Total risk-based capital:
	TCF	2,107,981		13.64		1,236,456		8		1,545,571		10
	TCF Bank	2,018,959		13.07		1,236,066		8		1,545,082		10
	N.A. Not Applicable.
	-1	The minimum and well-capitalized requirements are determined by the Federal Reserve Board for TCF and by the OCC for TCF Bank pursuant to the Federal Deposit Insurance Corporation Improvement Act of 1991.
	-2	The minimum Tier 1 leverage ratio for bank holding companies and banks is 3.0 or 4.0 percent, depending on factors specified in regulations issued by federal banking agencies.

Stock_Compensation

Stock Compensation	12 Months Ended
	Dec. 31, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock Compensation	Stock Compensation
	The TCF Financial Incentive Stock Program (the "Program") was adopted to enable TCF to attract and retain key personnel. At December 31, 2014, there were 2,754,016 shares reserved for issuance under the Program.
	At December 31, 2014, there were 1,080,916 shares of performance-based restricted stock outstanding that will vest only if certain return on asset goals, loan volumes and credit quality metrics and service conditions are achieved. Failure to achieve the performance and service conditions will result in all or a portion of the shares being forfeited. Awards of service-based restricted stock vest over periods from one year to five years.
	Information about restricted stock is summarized as follows.
		At or For the Year Ended December 31,
	(Dollars in thousands)	2014				2013			2012
	Compensation expense for restricted stock	$	8,690			$	10,467		$	10,934
	Unrecognized stock compensation expense for restricted stock awards and options	22,532				14,482			19,530
	Tax benefit recognized for stock compensation expense	3,424				4,034			4,259
	Weighted average amortization (years)	2.6				1.6			2.1
	TCF has also issued stock options under the Program that generally become exercisable over a period of one to ten years from the date of the grant and expire after ten years. All outstanding options have a fixed exercise price equal to the market price of TCF common stock on the date of grant.
	Valuation and related assumption information for TCF's stock option plans related to options issued in 2008 is presented below and no stock options were subsequently issued through December 31, 2014.
	Expected volatility				28.50%
	Weighted-average volatility				28.50%
	Expected dividend yield				3.50%
	Expected term (years)	6.25		-	6.75
	Risk-free interest rate	2.58	%	-	2.91%
	The following table reflects TCF's restricted stock and stock option transactions under the Program since December 31, 2011.
		Restricted Stock												Stock Options
		Shares			Price Range							Weighted-		Shares		Price Range					Weighted-	Weighted-
												Average									Average	Average
												Grant Date									Remaining	Exercise
												Fair Value									Contractual	Price
																					Life in Years
	Outstanding at December 31, 2011	2,284,114			$	6.16		-		$	28.64	$	12.95	2,198,744		$	12.85	-	$	15.75	5.72	$	14.43
	Granted	1,769,700			7.73			-		11.56		9.27		—		—		-	—		—	—
	Forfeited/canceled	(322,908	)		7.73			-		28.02		10.13		(121,640	)	15.75		-	15.75		—	15.75
	Vested	(518,671	)		7.57			-		28.64		13.42		—		—		-	—		—	—
	Outstanding at December 31, 2012	3,212,235			6.16			-		25.18		11.13		2,077,104		12.85		-	15.75		4.22	14.35
	Granted	493,650			12.47			-		15.17		13.55		—		—		-	—		—	—
	Forfeited/canceled	(120,313	)		9.65			-		17.37		12.75		(451,104	)	15.75		-	15.75		—	15.75
	Vested	(230,277	)		9.48			-		25.18		16.04		—		—		-	—		—	—
	Outstanding at December 31, 2013	3,355,295			6.16			-		15.17		11.09		1,626,000		12.85		-	15.75		4.36	13.97
	Granted	1,120,750			13.84			-		16.02		15.61		—		—		-	—		—	—
	Exercised	—			—			-		—		—		(47,000	)	15.75		-	15.75		—	15.75
	Forfeited/canceled	(108,490	)		6.8			-		15.79		13.06		—		—		-	—		—	—
	Vested	(1,509,061	)		8.35			-		14.9		11.21		—		—		-	—		—	—
	Outstanding at December 31, 2014	2,858,494			6.16			-		16.02		12.73		1,579,000		12.85		-	15.75		2.98	13.91
	Exercisable at December 31, 2014	N.A.										N.A.		1,579,000		12.85		-	15.75			13.91
	N.A. Not Applicable.

Employee_Benefit_Plans

Employee Benefit Plans	12 Months Ended
	Dec. 31, 2014
Compensation and Retirement Disclosure [Abstract]
Employee Benefit Plans	Employee Benefit Plans
	Employees Stock Purchase Plan The TCF Employees Stock Purchase Plan (the "ESPP"), a qualified 401(k) and employee stock ownership plan, generally allows participants to make contributions of up to 50% of their covered compensation on a tax-deferred basis, subject to the annual covered compensation limitation imposed by the Internal Revenue Service ("IRS"). TCF matches the contributions of all participants with TCF common stock at the rate of 50 cents per dollar for employees with one through four years of service up to a maximum company contribution of 3.0% of the employee's covered compensation, 75 cents per dollar for employees with five through nine years of service up to a maximum company contribution of 4.5% of the employee's covered compensation and $1 per dollar for employees with ten or more years of service up to a maximum company contribution of 6.0% of the employee's covered compensation, subject to the annual covered compensation limitation imposed by the IRS. Employee contributions vest immediately while the Company's matching contributions are subject to a graduated vesting schedule based on an employee's years of service with full vesting after five years. Employees have the opportunity to diversify and invest their account balance, including matching contributions, in various mutual funds or TCF common stock. At December 31, 2014, the fair value of the assets in the ESPP totaled $244.0 million and included $139.6 million invested in TCF common stock. Dividends on TCF common shares held in the ESPP reduce retained earnings and the shares are considered outstanding for computing earnings per share. The Company's matching contributions are expensed when made. TCF's contributions to the ESPP were $9.6 million in 2014, $8.9 million in 2013 and $8.0 million in 2012.
	Pension Plan The TCF Cash Balance Pension Plan (the "Pension Plan") is a qualified defined benefit plan covering eligible employees who are at least 21 years old and have completed a year of eligible service with TCF. Employees hired after June 30, 2004 are not eligible to participate in the Pension Plan. Effective March 31, 2006, TCF amended the Pension Plan to discontinue compensation credits for all participants. Interest credits will continue to be paid until participants' accounts are distributed from the Pension Plan. Each month TCF credits participants' accounts with interest on the account balance based on the five-year Treasury rate plus 25 basis points determined at the beginning of each year. All participant accounts are vested.
	The measurement of the projected benefit obligation, prepaid pension asset, pension liability and annual pension expense involves complex actuarial valuation methods and the use of actuarial and economic assumptions. Due to the long-term nature of the Pension Plan obligation, actual results may differ significantly from the actuarial-based estimates. Differences between estimates and actual experience are recorded in the year they arise. TCF closely monitors all assumptions and updates them annually. The Company does not consolidate the assets and liabilities associated with the Pension Plan.
	Postretirement Plan TCF provides health care benefits for eligible retired employees (the "Postretirement Plan"). Effective January 1, 2000, TCF modified the Postretirement Plan for employees not yet eligible for benefits under the Postretirement Plan by eliminating the Company subsidy. The Postretirement Plan provisions for full-time and retired employees then eligible for these benefits were not changed. Employees retiring after December 31, 2009 are no longer eligible to participate in the Postretirement Plan. The Postretirement Plan is not funded.
	The information set forth in the following tables is based on current actuarial reports using the measurement date of December 31 for TCF's Pension Plan and Postretirement Plan.
	The following table sets forth the status of the Pension Plan and the Postretirement Plan.
		Pension Plan								Postretirement Plan
		Year Ended December 31,
	(In thousands)	2014				2013				2014			2013
	Change in benefit obligation:
	Benefit obligation, beginning of period	$	41,870			$	45,037			$	5,217		$	6,675
	Interest cost on projected benefit obligation	1,587				1,292				198			174
	Actuarial (gain) loss	1,862				(2,196		)		(63		)	(1,241		)
	Benefits paid	(5,829		)		(2,263		)		(368		)	(391		)
	Projected benefit obligation, end of period	39,490				41,870				4,984			5,217
	Change in fair value of plan assets:
	Fair value of plan assets, beginning of period	51,018				53,617				—			—
	Actual gain (loss) on plan assets	(511		)		(336		)		—			—
	Benefits paid	(5,829		)		(2,263		)		(368		)	(391		)
	TCF contributions	—				—				368			391
	Fair value of plan assets, end of period	44,678				51,018				—			—
	Funded status of plans, end of period	$	5,188			$	9,148			$	(4,984	)	$	(5,217	)
	Amounts recognized in the Consolidated Statements of Financial Condition:
	Prepaid (accrued) benefit cost, end of period	$	5,188			$	9,148			$	(4,984	)	$	(5,217	)
	Prior service cost included in accumulated other comprehensive loss	—				—				(331		)	(378		)
	Accumulated other comprehensive loss, before tax	—				—				(331		)	(378		)
	Total recognized asset (liability)	$	5,188			$	9,148			$	(5,315	)	$	(5,595	)
	The accumulated benefit obligation for the Pension Plan was $39.5 million and $41.9 million at December 31, 2014 and 2013, respectively.
	TCF's Pension Plan investment policy states that assets may be invested in direct fixed income securities to include cash, money market mutual funds, U.S. Treasury securities, U.S. Government-sponsored enterprises and indirect fixed income investment securities made in fund form (mutual fund or institutional fund) where the fund invests in fixed income securities in investment grade corporate credits, non-investment grade floating-rate bank loans and non-investment grade bonds. The fair value of Level 1 assets are based upon prices obtained from independent pricing sources for the same assets traded in active markets. The fair value of the collective investment fund and the mortgage-backed securities categorized as Level 2 assets are based on prices obtained from independent pricing sources that are based on observable transactions of similar instruments, but not quoted markets. There were no assets that are valued on a recurring basis as Level 3 assets.
	The following table presents the balances of TCF's Pension Plan investments at fair value on a recurring basis.
		Pension Plan
		Year Ended December 31,
	(In thousands)	2014					2013
	Level 1:
	U.S. Treasury bills	$	—				$	47,999
	Fixed income mutual funds	22,532					—
	Money market mutual funds	16,088					3,019
	Cash	71					—
	Level 2:
	Collective investment fund	4,961			—		—
	Mortgage-backed securities	1,026					—
	Total Pension Plan assets held in trust	$	44,678				$	51,018
	The following table sets forth the changes recognized in accumulated other comprehensive loss that are attributed to the Postretirement Plan.
		Postretirement Plan
		Year Ended December 31,
	(In thousands)	2014				2013				2012
	Accumulated other comprehensive loss at the beginning of the year	$	(378	)		$	(424	)		$	(301	)
	Prior service cost	—				—				(151		)
	Amortization (recognized in net periodic benefit cost):
	Prior service credit	47				46				28
	Total recognized in other comprehensive income (loss)	47				46				(123		)
	Accumulated other comprehensive loss at end of year, before tax	$	(331	)		$	(378	)		$	(424	)
	The Pension Plan does not have any accumulated other comprehensive loss.
	The measurement dates used for determining the Pension Plan and the Postretirement Plan projected and accumulated benefit obligations and the dates used to value plan assets were December 31, 2014 and 2013. The discount rates used to measure the benefit obligation of the Pension Plan and the Postretirement Plan were 3.25% and 4.0% for the years ended December 31, 2014 and 2013, respectively.
	The following tables set forth the net periodic benefit plan (income) cost included in compensation and employee benefits expense for the Pension Plan and the Postretirement Plan.
		Pension Plan
		Year Ended December 31,
	(In thousands)	2014				2013				2012
	Interest cost	$	1,587			$	1,292			$	1,763
	Loss on plan assets	511				336				277
	Recognized actuarial (gain) loss	1,862				(2,196		)		289
	Net periodic benefit plan (income) cost	$	3,960			$	(568	)		$	2,329
		Postretirement Plan
	Year Ended December 31,
(In thousands)	2014				2013				2012
Interest cost	$	198			$	174			$	293
Recognized actuarial (gain) loss	(63		)		(1,241		)		(721		)
Amortization of prior service cost	(47		)		(46		)		(28		)
Net periodic benefit plan (income) cost	$	88			$	(1,113	)		$	(456	)
Pension Plan actual return on plan assets, net of administrative expenses was a loss of 1.0% for the year ended December 31, 2014 and a loss of 0.6% for the year ended December 31, 2013. The expected actuarial return on plan assets was a gain of $0.7 million and the actual loss on plan assets was $0.5 million and increased net periodic benefit cost for the year ended December 31, 2014. The expected actuarial return on plan assets was a gain of $0.8 million and the actual loss on plan assets was $0.3 million and increased net periodic benefit cost for the year ended December 31, 2013.
The discount rate and expected long-term rate of return on plan assets used to determine the estimated net benefit plan cost were as follows.
	Pension Plan									Postretirement Plan
	Year Ended December 31,									Year Ended December 31,
Assumptions used to determine estimated net benefit plan cost	2014			2013			2012			2014		2013			2012
Discount rate	4	%		3	%		4	%		4	%	2.75	%		4	%
Expected long-term rate of return on plan assets	1.5			1.5			1.5			N.A.		N.A.			N.A.
N.A. Not Applicable.
Prior service credits of TCF's Postretirement Plan totaling $46 thousand are included within accumulated other comprehensive loss at December 31, 2014 and are expected to be recognized as components of net periodic benefit cost during 2015.
The actuarial assumptions used in the Pension Plan valuation are reviewed annually. The expected long-term rate of return on plan assets is determined by reference to historical market returns and future expectations. The 10-year average return of the index consistent with the Pension Plan's current investment strategy was 3.2%, net of administrative expenses. A 1.0% difference in the expected return on plan assets would result in a $0.4 million change in net periodic pension expense.
The discount rate used to determine TCF's pension and postretirement benefit obligations as of December 31, 2014 and 2013 was determined by matching estimated benefit cash flows to a yield curve derived from corporate bonds rated AA by either Moody's or Standard and Poor's. Bonds containing call or put provisions were excluded. The average estimated duration of TCF's Pension Plan and Postretirement Plan varied between seven and eight years.
Included within the net periodic benefit cost for the Pension Plan are recognized actuarial gains and losses. The decrease in the discount rate from 4.0% at December 31, 2013 to 3.25% at December 31, 2014 increased net periodic benefit cost by $1.9 million during 2014. Updated mortality tables at December 31, 2014 and various plan participant census changes decreased the 2014 net periodic benefit cost by $32 thousand.
Included within the net periodic benefit cost for the Postretirement Plan are recognized actuarial gains and losses. The Postretirement Plan change in actuarially estimated cost per participant as of December 31, 2014 reduced net periodic benefit cost by $0.6 million. The decrease in the discount rate from 4.0% at December 31, 2013 to 3.25% at December 31, 2014 increased the net periodic benefit cost by $0.3 million. Updated mortality tables at December 31, 2014 and various plan demographic changes increased the net periodic benefit obligation by $0.3 million.
For 2014, TCF was eligible to contribute up to $10.9 million to the Pension Plan until the 2014 federal income tax return extension due date under various IRS funding methods. During 2014, TCF made no cash contributions to the Pension Plan. TCF does not expect to be required to contribute to the Pension Plan in 2015. TCF expects to contribute $0.5 million to the Postretirement Plan in 2015. TCF contributed $0.4 million to the Postretirement Plan for the year ended December 31, 2014. TCF currently has no plans to pre-fund the Postretirement Plan in 2015.
The following are expected future benefit payments used to determine projected benefit obligations.
(In thousands)	Pension Plan				Postretirement Plan
2015	$	4,209			$	505
2016	3,549				486
2017	2,881				466
2018	3,036				445
2019	3,138				424
2020 - 2024	12,284				1,801
The following table presents assumed health care cost trend rates for the Postretirement Plan at December 31, 2014 and 2013.
	2014			2013
Health care cost trend rate assumed for next year	5.8	%		6	%
Final health care cost trend rate	5	%		5	%
Year that final health care trend rate is reached	2023			2023
Assumed health care cost trend rates have an effect on the amounts reported for the Postretirement Plan. A 1.0% change in assumed health care cost trend rates would have the following effect.
	1-Percentage-Point
(In thousands)	Increase				Decrease
Effect on total service and interest cost components	$	9			$	(9	)
Effect on postretirement benefits obligations	217				(196		)

Financial_Instruments_with_Off

Financial Instruments with Off-Balance Sheet Risk	12 Months Ended
	Dec. 31, 2014
Financial Instruments with Off-Balance Sheet Risk
Financial Instruments with Off-Balance Sheet Risk	Financial Instruments with Off-Balance Sheet Risk
	TCF is a party to financial instruments with off-balance sheet risk, primarily to meet the financing needs of its customers. These financial instruments, which are issued or held for purposes other than trading, involve elements of credit and interest-rate risk in excess of the amount recognized in the Consolidated Statements of Financial Condition.
	TCF's exposure to credit loss, in the event of non-performance by the counterparty to the financial instrument, for commitments to extend credit and standby letters of credit is represented by the contractual amount of the commitments. TCF uses the same credit policies in making these commitments as it does for making direct loans. TCF evaluates each customer's creditworthiness on a case-by-case basis. The amount of collateral obtained is based on a credit evaluation of the customer.
	Financial instruments with off-balance sheet risk are summarized as follows.
		At December 31,
	(In thousands)	2014		2013
	Commitments to extend credit:
	Consumer real estate and other	$	1,314,826	$	1,274,006
	Commercial	609,618		482,777
	Leasing and equipment finance	140,261		158,321
	Total commitments to extend credit	2,064,705		1,915,104
	Standby letters of credit and guarantees on industrial revenue bonds	14,676		13,364
	Total	$	2,079,381	$	1,928,468
	Commitments to Extend Credit Commitments to extend credit are agreements to lend provided there is no violation of any condition in the contract. These commitments generally have fixed expiration dates or other termination clauses and may require payment of a fee. Since certain of the commitments are expected to expire without being drawn upon, the total commitment amounts do not necessarily represent future cash requirements. Collateral to secure any funding of these commitments predominantly consists of residential and commercial real estate.
	Standby Letters of Credit and Guarantees on Industrial Revenue Bonds Standby letters of credit and guarantees on industrial revenue bonds are conditional commitments issued by TCF guaranteeing the performance of a customer to a third party. These conditional commitments expire in various years through 2018. Collateral held consists primarily of commercial real estate mortgages. Since the conditions under which TCF is required to fund these commitments may not materialize, the cash requirements are expected to be less than the total outstanding commitments.

Derivative_Instruments

Derivative Instruments	12 Months Ended
	Dec. 31, 2014
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments	Derivative Instruments
	All derivative instruments are recognized within other assets or other liabilities at fair value within the Consolidated Statements of Financial Condition. The value of derivative instruments will vary over their contractual terms as the related underlying rates fluctuate. The accounting for changes in the fair value of a derivative instrument depends on whether or not the contract has been designated and qualifies as a hedge. To qualify as a hedge, a contract must be highly effective at reducing the risk associated with the exposure being hedged. In addition, for a contract to be designated as a hedge, the risk management objective and strategy must be documented at inception. Hedge documentation must also identify the hedging instrument, the asset or liability and type of risk to be hedged and how the effectiveness of the contract is assessed prospectively and retrospectively. To assess effectiveness, TCF uses statistical methods such as regression analysis. A contract that has been, and is expected to continue to be, effective at offsetting changes in cash flows or the net investment must be assessed and documented at least quarterly. If it is determined that a contract is not highly effective at hedging the designated exposure, hedge accounting is discontinued.
	Upon origination of a derivative instrument, the contract is designated either as a hedge of a forecasted transaction or the variability of cash flows to be paid related to a recognized asset or liability ("cash flow hedge"), a hedge of the volatility of an investment in foreign operations driven by changes in foreign currency exchange rates ("net investment hedge"), or is not designated as a hedge. Changes in net investment hedges recorded within other comprehensive income (loss) are subsequently reclassified to non-interest expense during the period in which the foreign investment is substantially liquidated or when other elements of the currency translation adjustment are reclassified to income. If a hedged forecasted transaction is no longer probable, hedge accounting is discontinued and any gain or loss included in other comprehensive income (loss) is reported in earnings immediately.
	Cash Flow Hedges TCF uses certain forward foreign exchange contracts to manage foreign exchange risk. Forward foreign exchange contracts represent agreements to exchange a foreign currency for U.S. dollars at an agreed-upon price and settlement date. Certain of these foreign exchange contracts were designated as cash flow hedges. TCF had no forward foreign exchange contracts designated as cash flow hedges at December 31, 2014 or 2013.
	Net Investment Hedges  Foreign exchange contracts, which include certain forward contracts that settle within 30 days, are used to manage the foreign exchange risk associated with the Company's net investment in TCF Commercial Finance Canada, Inc., a wholly-owned indirect Canadian subsidiary of TCF Bank.
	Derivatives Not Designated as Hedges  TCF executes interest rate swaps with commercial banking customers to facilitate their respective risk management strategies. Those interest rate swaps are simultaneously hedged by offsetting interest rate swaps that TCF executes with a third party, such that TCF minimizes its net risk exposure resulting from such transactions. As the interest rate swaps associated with this program do not meet hedge accounting requirements, changes in the fair value of both the customer swaps and the offsetting swaps are reflected in non-interest income. These contracts have original fixed maturity dates ranging from three to ten years.
	During the second quarter of 2012, TCF sold its Visa® Class B stock. In conjunction with the sale, TCF and the purchaser entered into a derivative transaction whereby TCF may receive or be required to make cash payments whenever the conversion ratio of the Visa Class B stock into Visa Class A stock is adjusted. The fair value of this derivative has been determined using estimated future cash flows using probability weighted scenarios for multiple estimates of Visa's aggregate exposure to covered litigation matters, which include consideration of amounts funded by Visa into its escrow account for the covered litigation matters. Changes, if any, in the valuation of this swap agreement, which has no determinable maturity date, are reflected in non-interest income.
	Certain of TCF's forward foreign exchange contracts are not designated as hedges and are generally settled within 30 days. Changes in the fair value of these foreign exchange contracts are reflected in non-interest expense.
	TCF enters into interest rate lock commitments in conjunction with certain consumer real estate loans. These interest rate lock commitments are agreements to extend credit under certain specified terms and conditions at fixed rates and have original lock expirations of up to 60 days. They are not designated as hedges and accordingly, changes in the valuation of these commitments are reflected in non-interest income.
	The following tables summarize TCF's outstanding derivative instruments as of December 31, 2014 and 2013. See Note 19, Fair Value Disclosures for additional information.
		At December 31, 2014
	(In thousands)	Notional			Gross Amounts		Gross Amounts			Net Amount
		Amount			Recognized		Offset			Presented(1)
	Derivative Assets:
	Net investment hedges	$	42,165		$	509	$	—		$	509
	Forward foreign exchange contracts not designated as hedges	275,962			2,702		(1,179		)	1,523
	Swap agreements	101,166			1,798		—			1,798
	Interest rate lock commitments	15,124			285		—			285
	Total derivative assets				$	5,294	$	(1,179	)	$	4,115
	Derivative Liabilities:
	Forward foreign exchange contracts not designated as hedges	$	189,310		$	177	$	(29	)	$	148
	Swap agreements	114,970			2,498		(2,498		)	—
	Total derivative liabilities				$	2,675	$	(2,527	)	$	148
		At December 31, 2013
	(In thousands)	Notional			Gross Amounts		Gross Amounts			Net Amount
		Amount			Recognized		Offset			Presented(1)
	Derivative Assets:
	Forward foreign exchange contracts not designated as hedges	$	98,847		$	151	$	(151	)	$	—
	Swap agreements	13,500			131		—			131
	Total derivative assets				$	282	$	(151	)	$	131
	Derivative Liabilities:
	Net investment hedges	$	32,761		$	87	$	—		$	87
	Forward foreign exchange contracts not designated as hedges	363,475			834		—			834
	Swap agreements	41,358			1,031		(1,031		)	—
	Total derivative liabilities				$	1,952	$	(1,031	)	$	921
	-1	All amounts were offset in the Consolidated Statements of Financial Condition.
	The following table summarizes the pre-tax impact of derivative activity within the Consolidated Statements of Income and the Consolidated Statements of Comprehensive Income, by accounting designation.
		Year Ended December 31,
	(In thousands)	2014			2013		2012
	Consolidated Statements of Income:
	Non-interest income:
	Swap agreements	$	(79	)	$	—	$	—
	Interest rate lock commitments	285			—		—
	Non-interest expense:
	Cash flow hedge	—			—		(6		)
	Forward foreign exchange contracts not designated as hedges	38,752			25,170		(7,524		)
	Net realized gain (loss)	$	38,958		$	25,170	$	(7,530	)
	Consolidated Statements of Comprehensive Income:
	Other comprehensive income (loss):
	Net investment hedges	$	3,126		$	1,625	$	(630	)
	Net unrealized gain (loss)	$	3,126		$	1,625	$	(630	)
	TCF executes all of its foreign exchange contracts in the over-the-counter market with large financial institutions pursuant to International Swaps and Derivatives Association, Inc. agreements. These agreements include credit risk-related features that enhance the creditworthiness of these instruments as compared with other obligations of the respective counterparty with whom TCF has transacted by requiring that additional collateral be posted under certain circumstances. The amount of collateral required depends on the contract and is determined daily based on market and currency exchange rate conditions.
	At December 31, 2014, credit risk-related contingent features existed on forward foreign exchange contracts with a notional value of $124.8 million. In the event TCF is rated less than BB- by Standard and Poor's, the contracts could be terminated or TCF may be required to provide approximately $2.5 million in additional collateral. There were no forward foreign exchange contracts containing credit risk-related features in a net liability position at December 31, 2014.
	At December 31, 2014, TCF had posted $5.1 million of cash collateral related to its swap agreements and had received $1.2 million of cash collateral related to its forward foreign exchange contracts.

Fair_Values_Disclosures

Fair Values Disclosures	12 Months Ended
	Dec. 31, 2014
Fair Value Disclosures [Abstract]
Fair Value Disclosures	Fair Value Disclosures
	TCF uses fair value measurements to record fair value adjustments to certain assets and liabilities and to determine fair value disclosures. The Company's fair values are based on the price that would be received upon the sale of an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. Securities available for sale, certain loans and leases held for sale, forward foreign exchange contracts, swap agreements, interest rate lock commitments, forward loan sales commitments and assets and liabilities held in trust for deferred compensation plans are recorded at fair value on a recurring basis. From time to time we may be required to record at fair value other assets on a non-recurring basis, such as certain securities held to maturity, loans, interest-only strips, other real estate owned and repossessed and returned assets. These non-recurring fair value adjustments typically involve application of lower-of-cost-or-market accounting or write-downs of individual assets.
	The following is a discussion of the fair value hierarchy and the valuation methodologies used for assets and liabilities recorded at fair value on a recurring or non-recurring basis and for estimating fair value of financial instruments not recorded at fair value.
	TCF groups its assets and liabilities measured at fair value in three levels, based on the markets in which the assets and liabilities are traded and the degree and reliability of estimates and assumptions used to determine fair value as follows: Level 1, which includes valuations that are based on prices obtained from independent pricing sources for the same instruments traded in active markets; Level 2, which includes valuations that are based on prices obtained from independent pricing sources that are based on observable transactions of similar instruments, but not quoted markets; and Level 3, for which valuations are generated from Company model-based techniques that use significant unobservable inputs. Such unobservable inputs reflect estimates of assumptions that market participants would use in pricing the asset or liability.
	Investments The carrying value of investments in FHLB stock and Federal Reserve Bank stock, categorized as Level 2, approximates fair value based on redemption at par value.
	Securities Held to Maturity Securities held to maturity consist primarily of securities of U.S. Government sponsored enterprises and federal agencies. The fair value of securities of U.S. Government sponsored enterprises and federal agencies, categorized as Level 2, is estimated using prices obtained from independent asset pricing services that are based on observable transactions, but not quoted markets. Management reviews the prices obtained from independent asset pricing services for unusual fluctuations and comparisons to current market trading activity. The fair value of certain other securities held to maturity, categorized as Level 3, is estimated based on discounted cash flows using current market rates and consideration of credit exposure or other internal pricing methods. There is no observable secondary market for these securities.
	Securities Available for Sale Securities available for sale consist primarily of securities of U.S. Government sponsored enterprises and federal agencies. The fair value of securities of U.S. Government sponsored enterprises and federal agencies, categorized as Level 2, is recorded using prices obtained from independent asset pricing services that are based on observable transactions, but not quoted markets. Management reviews the prices obtained from independent asset pricing services for unusual fluctuations and comparisons to current market trading activity. The fair value of other securities, categorized as Level 1, is determined using quoted prices from the New York Stock Exchange.
	Loans and Leases Held for Sale Loans and leases held for sale are generally carried at the lower of cost or fair value. The cost of loans held for sale includes the unpaid principal balance, net of deferred loan fees and costs. Estimated fair values are based upon recent loan sale transactions and any available price quotes on loans with similar coupons, maturities and credit quality. Certain other loans and leases held for sale are recorded at fair value under the elected fair value option. TCF relies on internal valuation models which utilize quoted investor prices to estimate the fair value of these loans. Loans and leases held for sale are categorized as Level 3.
	Loans The fair value of loans, categorized as Level 3, is estimated based on discounted expected cash flows and recent sales of similar loans. The discounted cash flows include assumptions for prepayment estimates over each loan's remaining life, consideration of the current interest rate environment compared with the weighted average rate of each portfolio, a credit risk component based on the historical and expected performance of each portfolio and a liquidity adjustment related to the current market environment. TCF also uses pricing data from recent sales of loans with similar risk characteristics as data points to validate the assumptions used in estimating the fair value of certain loans.
	Loans for which repayment is expected to be provided solely by the value of the underlying collateral, categorized as Level 3 and recorded at fair value on a non-recurring basis, are valued based on the fair value of that collateral less estimated selling costs. Such loans include impaired loans as well as certain delinquent non-accrual consumer real estate and auto finance loans. The fair value of the collateral is determined based on internal estimates and assessments provided by third-party appraisers.
	Forward Foreign Exchange Contracts TCF's forward foreign exchange contracts are currency contracts executed in over-the-counter markets and are recorded at fair value using a cash flow model that includes key inputs such as foreign exchange rates and, in accordance with GAAP, an assessment of the risk of counterparty non-performance. The risk of counterparty non-performance is based on external assessments of credit risk. The fair value of these contracts, categorized as Level 2, is based on observable transactions, but not quoted markets.
	Swap Agreements TCF executes interest rate swaps with commercial banking customers to facilitate the customer's risk management strategy. These interest rate swaps are simultaneously hedged by offsetting interest rate swaps TCF executes with a third party, such that TCF minimizes its net risk exposure resulting from such transactions. These derivative instruments are recorded at fair value. The fair value of these swap agreements, categorized as Level 2, is determined using a cash flow model which considers the forward curve, the discount curve and credit valuation adjustments related to counterparty and borrower non-performance risk. TCF also entered into a swap agreement related to the sale of TCF's Visa Class B stock, categorized as Level 3. The fair value of the Visa swap agreement is based upon TCF's estimated exposure related to the Visa covered litigation through a probability analysis of the funding and estimated settlement amounts.
	Interest Rate Lock Commitments and Forward Loan Sales Commitments TCF's interest rate lock commitments are derivative instruments which are recorded at fair value. The related forward loan sales commitments to sell the resulting loans held for sale are also carried at fair value under the elected fair value option. TCF relies on internal valuation models to estimate the fair value of these instruments. The valuation models utilize estimated rates of successful loan closings and quoted investor prices. While these models use both Level 2 and 3 inputs, TCF has determined that the majority of the inputs significant in the valuation of these commitments fall within Level 3 and therefore they are categorized as Level 3.
	Interest-Only Strips The fair value of interest-only strips, categorized as Level 3, represents the present value of future cash flows retained by TCF on certain assets. TCF uses available market data, along with its own empirical data and discounted cash flow models, to arrive at the estimated fair value of its interest-only strips. The present value of the estimated expected future cash flows to be received is determined by using discount, loss and prepayment rates that TCF believes are commensurate with the risks associated with the cash flows and what a market participant would use. These assumptions are inherently subject to volatility and uncertainty and, as a result, the estimated fair value of the interest-only strips may fluctuate significantly from period to period.
	Other Real Estate Owned and Repossessed and Returned Assets The fair value of other real estate owned is based on independent appraisals, real estate brokers' price opinions or automated valuation methods, less estimated selling costs. Certain properties require assumptions that are not observable in an active market in the determination of fair value. The fair value of repossessed and returned assets is based on available pricing guides, auction results or price opinions, less estimated selling costs. Assets acquired through foreclosure, repossession or returned to TCF are initially recorded at the lower of the loan or lease carrying amount or fair value less estimated selling costs at the time of transfer to other real estate owned or repossessed and returned assets. Other real estate owned and repossessed and returned assets were written down $14.8 million and $15.6 million, which was included in foreclosed real estate and repossessed assets, net expense for the years ended December 31, 2014 and 2013, respectively.
	Deposits The fair value of checking, savings and money market deposits, categorized as Level 1, is deemed equal to the amount payable on demand. The fair value of certificates of deposit, categorized as Level 2, is estimated based on discounted cash flows using currently offered market rates. The intangible value of long-term relationships with depositors is not taken into account in the fair values disclosed.
	Long-term Borrowings The fair value of TCF's long-term borrowings, categorized as Level 2, is estimated based on observable market prices and discounted cash flows using interest rates for borrowings of similar remaining maturities and characteristics. The fair value of other long-term borrowings, categorized as Level 3, is based on unobservable inputs determined at the time of origination.
	Assets and Liabilities Held in Trust for Deferred Compensation Plans Assets held in trust for deferred compensation plans include investments in publicly traded stocks, excluding TCF common stock reported in treasury and other equity, and U.S. Treasury notes. The fair value of these assets, categorized as Level 1, is based upon prices obtained from independent asset pricing services based on active markets. The fair value of the liabilities equals the fair value of the assets.
	Financial Instruments with Off-Balance Sheet Risk The fair value of TCF's commitments to extend credit and standby letters of credit, categorized as Level 2, is estimated using fees currently charged to enter into similar agreements, as commitments and standby letters of credit similar to TCF's are not actively traded. Substantially all commitments to extend credit and standby letters of credit have floating interest rates and do not expose TCF to interest rate risk; therefore fair value is approximately equal to carrying value.
	The following tables present the balances of assets and liabilities measured at fair value on a recurring and non-recurring basis.
		Fair Value Measurements at December 31, 2014
	(In thousands)	Level 1			Level 2			Level 3			Total
	Recurring Fair Value Measurements:
	Securities available for sale:
	Mortgage-backed securities:
	U.S. Government sponsored enterprises and federal agencies	$	—		$	463,239		$	—		$	463,239
	Other	—			—			55			55
	Loans and leases held for sale	—			—			3,308			3,308
	Forward foreign exchange contracts(1)	—			3,211			—			3,211
	Swap agreements(1)	—			1,798			—			1,798
	Interest rate lock commitments(1)	—			—			285			285
	Forward loan sales commitments	—			—			19			19
	Assets held in trust for deferred compensation plans	18,703			—			—			18,703
	Total assets	$	18,703		$	468,248		$	3,667		$	490,618
	Forward foreign exchange contracts(1)	$	—		$	177		$	—		$	177
	Swap agreements(1)	—			1,877			621			2,498
	Forward loan sales commitments	—			—			42			42
	Liabilities held in trust for deferred compensation plans	18,703			—			—			18,703
	Total liabilities	$	18,703		$	2,054		$	663		$	21,420
	Non-recurring Fair Value Measurements:
	Securities held to maturity	$	—		$	—		$	1,516		$	1,516
	Loans	—			—			164,897			164,897
	Interest-only strips	—			—			41,204			41,204
	Other real estate owned:
	Consumer	—			—			40,502			40,502
	Commercial	—			4,839			8,866			13,705
	Repossessed and returned assets	—			1,563			1,425			2,988
	Total non-recurring fair value measurements	$	—		$	6,402		$	258,410		$	264,812
		Fair Value Measurements at December 31, 2013
	(In thousands)	Level 1			Level 2			Level 3			Total
	Recurring Fair Value Measurements:
	Securities available for sale:
	Mortgage-backed securities:
	U.S. Government sponsored enterprises and federal agencies	$	—		$	548,037		$	—		$	548,037
	Other	—			—			93			93
	Other securities	2,934			—			—			2,934
	Forward foreign exchange contracts(1)	—			151			—			151
	Swap agreements(1)	—			131			—			131
	Assets held in trust for deferred compensation plans	16,724			—			—			16,724
	Total assets	$	19,658		$	548,319		$	93		$	568,070
	Forward foreign exchange contracts(1)	$	—		$	921		$	—		$	921
	Swap agreements(1)	—			132			899			1,031
	Liabilities held in trust for deferred compensation plans	16,724			—			—			16,724
	Total liabilities	$	16,724		$	1,053		$	899		$	18,676
Non-recurring Fair Value Measurements:
Securities held to maturity	$	—		$	—		$	1,902		$	1,902
Loans	—			—			214,183			214,183
Interest-only strips	—			—			33,098			33,098
Other real estate owned:
Consumer	—			—			40,355			40,355
Commercial	—			—			14,088			14,088
Repossessed and returned assets	—			1,537			730			2,267
Total non-recurring fair value measurements	$	—		$	1,537		$	304,356		$	305,893
-1	As permitted under GAAP, TCF has elected to net derivative receivables and derivative payables with the related cash collateral received and paid when a legally enforceable master netting agreement exists. For purposes of this table, the derivative receivable and derivative payable balances are presented gross of this netting adjustment.
Management assesses the appropriate classification of financial assets and liabilities within the fair value hierarchy by monitoring the level of availability of observable market information. Changes in markets or economic conditions, as well as changes to Company valuation models may require the transfer of financial instruments from one fair value level to another. Such transfers, if any, are recorded at the fair values as of the beginning of the quarter in which the transfer occurred. TCF had no transfers in the years ended December 31, 2014 and 2013, and transferred $1.1 million of securities available for sale from Level 3 to Level 1 in the year ended December 31, 2012.
The following table presents changes in Level 3 assets and liabilities measured at fair value on a recurring basis.
(In thousands)	Securities Available			Loans and Leases Held for Sale			Interest			Forward Loan Sales Commitments			Swap Agreements
	for Sale						Rate Lock
							Commitments
Asset (liability) balance, December 31, 2011	$	1,450		$	—		$	—		$	—		$	—
Transfers out of Level 3	(1,098		)	—			—			—			—
Total net losses included in:
Net loss	—			—			—			—			(150		)
Other comprehensive loss	(100		)	—			—			—			—
Purchases	—			—			—			—			(1,434		)
Principal paydowns / settlements	(125		)	—			—			—			357
Asset (liability) balance, December 31, 2012	127			—			—			—			(1,227		)
Principal paydowns / settlements	(34		)	—			—			—			328
Asset (liability) balance, December 31, 2013	93			—			—			—			(899		)
Total net gains (losses) included in:
Net income	—			72			285			(23		)	(47		)
Sales	—			(39,246		)	—			—			—
Purchases / originations	—			42,482			—			—			—
Principal paydowns / settlements	(38		)	—			—			—			325
Asset (liability) balance, December 31, 2014	$	55		$	3,308		$	285		$	(23	)	$	(621	)
Fair Value Option
In the third quarter of 2014, TCF initiated a correspondent lending program in which TCF Bank originates consumer mortgage loans and sells them to a wholesale partner. TCF elected the fair value option for these loans. This election facilitates the offsetting of changes in fair values of the loans held for sale and the derivative financial instruments used to economically hedge them. The following table presents the difference between the aggregate fair value and aggregate unpaid principal balance of these loans held for sale as of December 31, 2014. There were no loans held for sale reported under the fair value option as of December 31, 2013.
(In thousands)	At December 31, 2014
Fair value carrying amount	$	3,308
Aggregate unpaid principal amount	3,205
Fair value carrying amount less aggregate unpaid principal	$	103
Differences between the fair value carrying amount and the aggregate unpaid principal balance include changes in fair value recorded at and subsequent to funding and gains and losses on the related loan commitment prior to funding. No
loans recorded under the fair value option were delinquent or on nonaccrual status at December 31, 2014. The net gain from initial measurement of the above loans and subsequent changes in fair value for loans outstanding was $0.9 million for the year ended December 31, 2014, and is included in gains on sales of consumer real estate loans, net. This amount excludes the impact from offsetting hedging arrangements which are also included in gains on sales of consumer real estate loans, net.
Disclosures About Fair Value of Financial Instruments
Management discloses the estimated fair value of financial instruments, both assets and liabilities on and off the balance sheet, for which it is practicable to estimate fair value. These fair value estimates were made at December 31, 2014 and 2013, based on relevant market information and information about the financial instruments. Fair value estimates are intended to represent the price at which an asset could be sold or a liability could be settled. However, given there is no active market or observable market transactions for many of the Company's financial instruments, the estimates of fair values are subjective in nature, involve uncertainties and include matters of significant judgment. Changes in assumptions could significantly affect the estimated values.
The following tables present the carrying amounts and estimated fair values of the Company's financial instruments, excluding short-term financial assets and liabilities as their carrying amounts approximate fair value and excluding financial instruments recorded at fair value on a recurring basis. This information represents only a portion of TCF's balance sheet and not the estimated value of the Company as a whole. Non-financial instruments such as the intangible value of TCF's branches and core deposits, leasing operations, goodwill, premises and equipment and the future revenues from TCF's customers are not reflected in this disclosure. Therefore, this information is of limited use in assessing the value of TCF.
				Estimated Fair Value at December 31, 2014
(In thousands)	Carrying Amount			Level 1			Level 2			Level 3			Total
Financial instrument assets:
Investments	$	85,492		$	—		$	85,492		$	—		$	85,492
Securities held to maturity	214,454			—			217,418			4,916			222,334
Loans and leases held for sale	132,266			—			—			139,370			139,370
Loans:
Consumer real estate	5,682,364			—			—			5,836,770			5,836,770
Commercial real estate	2,624,255			—			—			2,575,625			2,575,625
Commercial business	533,410			—			—			512,083			512,083
Equipment finance	1,806,808			—			—			1,787,271			1,787,271
Inventory finance	1,877,090			—			—			1,864,786			1,864,786
Auto finance	1,915,061			—			—			1,927,384			1,927,384
Other	24,144			—			—			18,724			18,724
Allowance for loan losses(1)	(164,169		)	—			—			—			—
Interest-only strips(2)	69,789			—			—			73,058			73,058
Total financial instrument assets	$	14,800,964		$	—		$	302,910		$	14,739,987		$	15,042,897
Financial instrument liabilities:
Deposits	$	15,449,882		$	12,400,693		$	3,063,850		$	—		$	15,464,543
Long-term borrowings	1,232,065			—			1,246,221			8,054			1,254,275
Total financial instrument liabilities	$	16,681,947		$	12,400,693		$	4,310,071		$	8,054		$	16,718,818
Financial instruments with off-balance sheet risk:(3)
Commitments to extend credit	$	25,885		$	—		$	25,885		$	—		$	25,885
Standby letters of credit	(47		)	—			(47		)	—			(47		)
Total financial instruments with off-balance sheet risk	$	25,838		$	—		$	25,838		$	—		$	25,838
-1	Expected credit losses are included in the estimated fair values.
-2	Carrying amounts are included in other assets.
-3	Positive amounts represent assets, negative amounts represent liabilities.
				Estimated Fair Value at December 31, 2013
(In thousands)	Carrying Amount			Level 1			Level 2			Level 3			Total
Financial instrument assets:
Investments	$	94,326		$	—		$	94,326		$	—		$	94,326
Securities held to maturity	19,912			—			14,610			5,302			19,912
Loans and leases held for sale	79,768			—			—			84,341			84,341
Loans:
Consumer real estate	6,339,326			—			—			6,279,328			6,279,328
Commercial real estate	2,743,697			—			—			2,673,825			2,673,825
Commercial business	404,655			—			—			392,947			392,947
Equipment finance	1,546,134			—			—			1,534,905			1,534,905
Inventory finance	1,664,377			—			—			1,653,345			1,653,345
Auto finance	1,239,386			—			—			1,256,357			1,256,357
Other	26,743			—			—			25,216			25,216
Allowance for loan losses(1)	(252,230		)	—			—			—			—
Interest-only strips(2)	84,561			—			—			85,265			85,265
Total financial instrument assets	$	13,990,655		$	—		$	108,936		$	13,990,831		$	14,099,767
Financial instrument liabilities:
Deposits	$	14,432,776		$	12,006,364		$	2,434,946		$	—		$	14,441,310
Long-term borrowings	1,483,325			—			1,496,017			10,838			1,506,855
Total financial instrument liabilities	$	15,916,101		$	12,006,364		$	3,930,963		$	10,838		$	15,948,165
Financial instruments with off-balance sheet risk:(3)
Commitments to extend credit	$	29,057		$	—		$	29,057		$	—		$	29,057
Standby letters of credit	(52		)	—			(52		)	—			(52		)
Total financial instruments with off-balance sheet risk	$	29,005		$	—		$	29,005		$	—		$	29,005
-1	Expected credit losses are included in the estimated fair values.
-2	Carrying amounts are included in other assets.
-3	Positive amounts represent assets, negative amounts represent liabilities.

Earnings_Per_Common_Share

Earnings Per Common Share	12 Months Ended
	Dec. 31, 2014
Earnings Per Share [Abstract]
Earnings Per Common Share	Earnings Per Common Share
	TCF's restricted stock awards that pay non-forfeitable common stock dividends meet the criteria of a participating security. Accordingly, earnings per share is calculated using the two-class method, under which earnings are allocated to both common shares and participating securities.
		At or For the Year Ended December 31,
	(Dollars in thousands, except per-share data)	2014			2013			2012
	Basic Earnings (Loss) Per Common Share:
	Net income (loss) attributable to TCF Financial Corporation	$	174,187		$	151,668		$	(212,884	)
	Preferred stock dividends	(19,388		)	(19,065		)	(5,606		)
	Net income (loss) available to common stockholders	154,799			132,603			(218,490		)
	Earnings allocated to participating securities	40			71			50
	Earnings (loss) allocated to common stock	$	154,759		$	132,532		$	(218,540	)
	Weighted-average shares outstanding	166,542,848			164,229,421			162,288,902
	Restricted stock	(2,961,413		)	(3,213,417		)	(3,020,094		)
	Weighted-average common shares outstanding for basic earnings (loss) per common share	163,581,435			161,016,004			159,268,808
	Basic earnings (loss) per common share	$	0.95		$	0.82		$	(1.37	)
	Diluted Earnings (Loss) Per Common Share:
	Earnings (loss) allocated to common stock	$	154,759		$	132,532		$	(218,540	)
	Weighted-average common shares outstanding used in basic earnings (loss) per common share calculation	163,581,435			161,016,004			159,268,808
	Net dilutive effect of:
	Non-participating restricted stock	250,499			719,459			—
	Stock options	252,892			191,092			—
	Weighted-average common shares outstanding for diluted earnings (loss) per common share	164,084,826			161,926,555			159,268,808
	Diluted earnings (loss) per common share	$	0.94		$	0.82		$	(1.37	)
	All shares of restricted stock are deducted from weighted-average shares outstanding for the computation of basic earnings per common share. Shares of performance-based restricted stock are included in the calculation of diluted earnings per common share, using the treasury stock method, at the beginning of the quarter in which the performance goals have been achieved. All other shares of restricted stock, which vest over specified time periods, stock options and warrants are included in the calculation of diluted earnings per common share, using the treasury stock method.
	For 2014, 2013 and 2012, there were 4.2 million, 3.8 million and 5.1 million, respectively, of outstanding shares related to non-participating restricted stock, stock options, and warrants that were not included in the computation of diluted earnings per share because they were anti-dilutive.

Other_Expense

Other Expense	12 Months Ended
	Dec. 31, 2014
Other Income and Expenses [Abstract]
Other Expense	Other Expense
	Other expense consisted of the following.
		Year Ended December 31,
	(In thousands)	2014		2013		2012
	Loan and lease processing	$	20,294	$	13,787	$	9,567
	Professional fees	18,949		18,642		13,608
	Card processing and issuance cost	16,588		15,868		15,586
	Outside processing	13,288		13,767		12,919
	Telecommunications	11,911		11,720		11,735
	Travel	11,481		12,810		11,740
	Other	87,393		81,183		88,742
	Total other expense	$	179,904	$	167,777	$	163,897

Business_Segments

Business Segments	12 Months Ended
	Dec. 31, 2014
Segment Reporting [Abstract]
Business Segments	Business Segments
	Lending, Funding and Support Services have been identified as reportable segments. Lending includes consumer real estate, commercial real estate and business lending, leasing and equipment finance, inventory finance and auto finance. Funding includes branch banking and treasury services. Support Services includes Holding Company and corporate functions that provide data processing, bank operations and other professional services to the operating segments.
	TCF evaluates performance and allocates resources based on each segment's net income or loss. The business segments follow GAAP as described in Note 1, Summary of Significant Accounting Policies. TCF generally accounts for inter-segment sales and transfers at cost.
	The following tables set forth certain information for each of TCF's reportable segments, including a reconciliation of TCF's consolidated totals.
	(In thousands)	Lending		Funding			Support Services			Eliminations and Other(1)			Consolidated
	At or For the Year Ended December 31, 2014:
	Net interest income	$	592,409	$	226,327		$	166		$	(3,273	)	$	815,629
	Provision for credit losses	92,800		2,937			—			—			95,737
	Non-interest income	211,166		220,568			140,779			(139,246		)	433,267
	Non-interest expense	426,290		434,141			147,549			(136,203		)	871,777
	Income tax expense (benefit)	102,398		3,722			(1,932		)	(4,422		)	99,766
	Income (loss) after income tax expense (benefit)	182,087		6,095			(4,672		)	(1,894		)	181,616
	Income attributable to non-controlling interest	7,429		—			—			—			7,429
	Preferred stock dividends	—		—			19,388			—			19,388
	Net income (loss) available to common stockholders	$	174,658	$	6,095		$	(24,060	)	$	(1,894	)	$	154,799
	Total assets	$	16,871,154	$	6,488,853		$	239,425		$	(4,204,821	)	$	19,394,611
	Revenues from external customers:
	Interest income	$	852,019	$	22,210		$	—		$	—		$	874,229
	Non-interest income	211,166		220,506			1,595			—			433,267
	Total	$	1,063,185	$	242,716		$	1,595		$	—		$	1,307,496
	At or For the Year Ended December 31, 2013:
	Net interest income	$	568,286	$	237,289		$	3		$	(2,954	)	$	802,624
	Provision for credit losses	115,408		2,960			—			—			118,368
	Non-interest income	168,387		235,238			136,584			(136,151		)	404,058
	Non-interest expense	401,326		442,557			139,864			(138,478		)	845,269
	Income tax expense (benefit)	76,663		9,750			8			(2,076		)	84,345
	Income (loss) after income tax expense (benefit)	143,276		17,260			(3,285		)	1,449			158,700
	Income attributable to non-controlling interest	7,032		—			—			—			7,032
	Preferred stock dividends	—		—			19,065			—			19,065
	Net income (loss) available to common stockholders	$	136,244	$	17,260		$	(22,350	)	$	1,449		$	132,603
	Total assets	$	16,197,449	$	7,862,779		$	228,863		$	(5,909,251	)	$	18,379,840
	Revenues from external customers:
	Interest income	$	840,250	$	24,290		$	—		$	—		$	864,540
	Non-interest income	168,387		235,185			486			—			404,058
	Total	$	1,008,637	$	259,475		$	486		$	—		$	1,268,598
	At or For the Year Ended December 31, 2012:
	Net interest income	$	524,358	$	258,283		$	41		$	(2,663	)	$	780,019
	Provision for credit losses	245,355		2,088			—			—			247,443
	Non-interest income	138,514		338,895			140,784			(127,770		)	490,423
	Non-interest expense	367,172		969,805			152,677			(127,100		)	1,362,554
	Income tax expense (benefit)	13,272		(135,432		)	(7,790		)	(2,908		)	(132,858		)
	Income (loss) after income tax expense (benefit)	37,073		(239,283		)	(4,062		)	(425		)	(206,697		)
	Income attributable to non-controlling interest	6,187		—			—			—			6,187
	Preferred stock dividends	—		—			5,606			—			5,606
	Net income (loss) available to common stockholders	$	30,886	$	(239,283	)	$	(9,668	)	$	(425	)	$	(218,490	)
	Total assets	$	15,694,693	$	7,249,958		$	148,513		$	(4,867,247	)	$	18,225,917
	Revenues from external customers:
	Interest income	$	842,718	$	41,905		$	—		$	—		$	884,623
	Non-interest income	138,514		338,848			13,061			—			490,423
	Total	$	981,232	$	380,753		$	13,061		$	—		$	1,375,046
	-1	Other includes the unallocated portion of pension and other postretirement benefits (expenses) attributable to the annual determination of actuarial gains and losses.

Parent_Company_Financial_Infor

Parent Company Financial Information	12 Months Ended
	Dec. 31, 2014
Condensed Financial Information of Parent Company Only Disclosure [Abstract]
Parent Company Financial Information	Parent Company Financial Information
	TCF Financial's (parent company only) condensed statements of financial condition as of December 31, 2014 and 2013 and the condensed statements of income and cash flows for the years ended December 31, 2014, 2013 and 2012 are as follows.
	Condensed Statements of Financial Condition
		At December 31,
	(In thousands)	2014			2013
	Assets:
	Cash and cash equivalents	$	71,781		$	62,775
	Investment in bank subsidiary	2,037,781			1,863,563
	Accounts receivable from bank subsidiary	13,862			21,706
	Other assets	12,628			19,498
	Total assets	$	2,136,052		$	1,967,542
	Liabilities and Equity:
	Other liabilities	$	14,403		$	14,574
	Total liabilities	14,403			14,574
	Equity	2,121,649			1,952,968
	Total liabilities and equity	$	2,136,052		$	1,967,542
	Condensed Statements of Income
		Year Ended December 31,
	(In thousands)	2014			2013			2012
	Interest income	$	365		$	419		$	355
	Interest expense	—			—			7,952
	Net interest income (expense)	365			419			(7,597		)
	Non-interest income:
	Dividends from TCF Bank	19,000			—			18,000
	Affiliate service fees	22,461			23,338			17,089
	Other	1,178			407			12,936
	Total non-interest income	42,639			23,745			48,025
	Non-interest expense:
	Compensation and employee benefits	21,193			22,108			14,703
	Occupancy and equipment	338			322			298
	Other	3,436			3,352			15,731
	Total non-interest expense	24,967			25,782			30,732
	Income (loss) before income tax benefit and equity in undistributed earnings of subsidiaries	18,037			(1,618		)	9,696
	Income tax benefit	52			309			2,766
	Income (loss) before equity in undistributed earnings of subsidiaries	18,089			(1,309		)	12,462
	Equity (deficit) in undistributed earnings of bank subsidiary	156,098			152,977			(225,346		)
	Net income (loss)	174,187			151,668			(212,884		)
	Preferred stock dividends	19,388			19,065			5,606
	Net income (loss) available to common stockholders	$	154,799		$	132,603		$	(218,490	)
	Condensed Statements of Cash Flows
		Year Ended December 31,
	(In thousands)	2014			2013			2012
	Cash flows from operating activities:
	Net income (loss)	$	174,187		$	151,668		$	(212,884	)
	Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
	(Equity) deficit in undistributed earnings of bank subsidiary	(156,098		)	(152,977		)	225,346
	(Gains) on sales of assets, net	(1,177		)	(350		)	(13,116		)
	Other, net	16,430			9,962			9,561
	Net cash provided by (used in) operating activities	33,342			8,303			8,907
	Cash flows from investing activities:
	Capital contributions to bank subsidiary	—			—			(192,000		)
	Proceeds from sales of securities available for sale	2,813			—			—
	Proceeds from sales of other securities	—			—			14,550
	Purchases of premises and equipment	(260		)	(148		)	(6		)
	Proceeds from sales of premises and equipment	91			—			—
	Other, net	—			869			—
	Net cash provided by (used in) investing activities	2,644			721			(177,456		)
	Cash flows from financing activities:
	Net proceeds from public offerings of preferred stock	—			—			263,240
	Dividends paid on preferred stock	(19,388		)	(19,065		)	(5,606		)
	Dividends paid on common stock	(32,731		)	(32,227		)	(31,904		)
	Redemption of trust preferred securities	—			—			(115,010		)
	Interest paid on trust preferred securities	—			—			(8,757		)
	Shares sold to TCF employee benefit plans	23,083			20,179			19,462
Stock compensation tax (expense) benefit	1,316			(473		)	(659		)
Exercise of stock options	740			—			—
Net cash provided by (used in) financing activities	(26,980		)	(31,586		)	120,766
Net change in cash and due from banks	9,006			(22,562		)	(47,783		)
Cash and due from banks at beginning of period	62,775			85,337			133,120
Cash and due from banks at end of period	$	71,781		$	62,775		$	85,337
TCF Financial's (parent company only) operations are conducted through its banking subsidiary, TCF Bank. As a result, TCF's cash flow and ability to make dividend payments to its common stockholders depend on the earnings of TCF Bank. The ability of TCF Bank to pay dividends or make other payments to TCF Financial is limited by its obligation to maintain sufficient capital and by other regulatory restrictions on dividends. At December 31, 2014, TCF Bank could pay a total of approximately $83.7 million in dividends to TCF without prior regulatory approval.

Accumulated_Other_Comprehensiv

Accumulated Other Comprehensive Income (Loss)	12 Months Ended
	Dec. 31, 2014
Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
Accumulated Other Comprehensive Income (Loss)	Accumulated Other Comprehensive Income (Loss)
	The components of other comprehensive income (loss) and the related tax effects are presented in the tables below.
	(In thousands)	Before Tax			Tax Effect			Net of Tax
	Year Ended December 31, 2014:
	Securities available for sale:
	Unrealized gains (losses) arising during the period	$	29,071		$	(10,932	)	$	18,139
	Reclassification of net (gains) losses to net income	(76		)	29			(47		)
	Net unrealized gains (losses)	28,995			(10,903		)	18,092
	Net investment hedges:
	Unrealized gains (losses) arising during the period	3,126			(1,181		)	1,945
	Foreign currency translation adjustment:(1)
	Unrealized gains (losses) arising during the period	(3,704		)	—			(3,704		)
	Recognized postretirement prior service cost:
	Reclassification of net (gains) losses to net income	(47		)	17			(30		)
	Total other comprehensive income (loss)	$	28,370		$	(12,067	)	$	16,303
	Year Ended December 31, 2013:
	Securities available for sale:
	Unrealized gains (losses) arising during the period	$	(61,177	)	$	23,053		$	(38,124	)
	Reclassification of net (gains) losses to net income	(860		)	324			(536		)
	Net unrealized gains (losses)	(62,037		)	23,377			(38,660		)
	Net investment hedges:
	Unrealized gains (losses) arising during the period	1,625			(614		)	1,011
	Foreign currency translation adjustment:(1)
	Unrealized gains (losses) arising during the period	(1,979		)	—			(1,979		)
	Recognized postretirement prior service cost:
	Reclassification of net (gains) losses to net income	(46		)	18			(28		)
	Total other comprehensive income (loss)	$	(62,437	)	$	22,781		$	(39,656	)
	Year Ended December 31, 2012:
	Securities available for sale:
	Unrealized gains (losses) arising during the period	$	19,794		$	(7,252	)	$	12,542
	Reclassification of net (gains) losses to net income	(89,879		)	32,745			(57,134		)
	Net unrealized gains (losses)	(70,085		)	25,493			(44,592		)
	Net investment hedges:
	Unrealized gains (losses) arising during the period	(630		)	239			(391		)
	Foreign currency translation adjustment:(1)
	Unrealized gains (losses) arising during the period	531			—			531
	Recognized postretirement prior service cost:
	Unrealized gains (losses) arising during the period	151			(66		)	85
	Reclassification of net (gains) losses to net income	(28		)	12			(16		)
	Total other comprehensive income (loss)	$	(70,061	)	$	25,678		$	(44,383	)
	-1	Foreign investments are deemed to be permanent in nature and therefore TCF does not provide for taxes on foreign currency translation adjustments.
	Reclassifications of net gains and net losses to net income related to securities available for sale were recorded in gains (losses) on securities, net in the Consolidated Statements of Income. The tax effect of these reclassifications was recorded in income tax expense (benefit) in the Consolidated Statements of Income. See Note 16, Employee Benefit Plans, for additional information regarding TCF's recognized postretirement prior service cost.
	Accumulated other comprehensive income (loss) balances are presented in the tables below.
	(In thousands)	Securities			Net			Foreign			Recognized			Total
		Available			Investment			Currency			Postretirement Prior
		for Sale			Hedges			Translation			Service Cost
								Adjustment
	At or For the Year Ended December 31, 2014:
	Balance, beginning of period	$	(26,983	)	$	591		$	(1,056	)	$	235		$	(27,213	)
	Other comprehensive income (loss)	18,139			1,945			(3,704		)	—			16,380
	Amounts reclassified from accumulated other comprehensive income (loss)	(47		)	—			—			(30		)	(77		)
	Net other comprehensive income (loss)	18,092			1,945			(3,704		)	(30		)	16,303
	Balance, end of period	$	(8,891	)	$	2,536		$	(4,760	)	$	205		$	(10,910	)
	At or For the Year Ended December 31, 2013:
	Balance, beginning of period	$	11,677		$	(420	)	$	923		$	263		$	12,443
	Other comprehensive income (loss)	(38,124		)	1,011			(1,979		)	—			(39,092		)
	Amounts reclassified from accumulated other comprehensive income (loss)	(536		)	—			—			(28		)	(564		)
	Net other comprehensive income (loss)	(38,660		)	1,011			(1,979		)	(28		)	(39,656		)
	Balance, end of period	$	(26,983	)	$	591		$	(1,056	)	$	235		$	(27,213	)
	At or For the Year Ended December 31, 2012:
	Balance, beginning of period	$	56,269		$	(29	)	$	392		$	194		$	56,826
	Other comprehensive income (loss)	12,542			(391		)	531			85			12,767
	Amounts reclassified from accumulated other comprehensive income (loss)	(57,134		)	—			—			(16		)	(57,150		)
	Net other comprehensive income (loss)	(44,592		)	(391		)	531			69			(44,383		)
Balance, end of period	$	11,677		$	(420	)	$	923		$	263		$	12,443

Litigation_Contingencies

Litigation Contingencies	12 Months Ended
	Dec. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
Litigation Contingencies	Litigation Contingencies
	From time to time, TCF is a party to legal proceedings arising out of its lending, leasing and deposit operations, including foreclosure proceedings and other collection actions as part of its lending and leasing collections activities. TCF may also be subject to enforcement actions brought by federal regulators, including the Securities and Exchange Commission ("SEC"), the Federal Reserve, the OCC and the Consumer Financial Protection Bureau. From time to time, borrowers and other customers, and employees and former employees, have also brought actions against TCF, in some cases claiming substantial damages. TCF and other financial services companies are subject to the risk of class action litigation. Litigation is often unpredictable and the actual results of litigation cannot be determined, and therefore the ultimate resolution of a matter and the possible range of loss associated with certain potential outcomes cannot be established. Based on our current understanding of TCF's pending legal proceedings, management does not believe that judgments or settlements arising from pending or threatened legal matters, individually or in the aggregate, would have a material adverse effect on the consolidated financial position, operating results or cash flows of TCF. TCF is also subject to regulatory examinations, and TCF's regulatory authorities may impose sanctions on TCF for failures related to regulatory compliance.

Summary_of_Significant_Account1

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2014
Accounting Policies [Abstract]
Consolidation	TCF Financial Corporation, a Delaware corporation ("we," "us," "our," "TCF" or the "Company"), is a national bank holding company based in Wayzata, Minnesota. Unless otherwise indicated, references herein to "TCF" include its direct and indirect subsidiaries. Its principal subsidiary, TCF National Bank ("TCF Bank"), is headquartered in South Dakota. References herein to "TCF Financial" refer to TCF Financial Corporation on an unconsolidated basis. All significant intercompany accounts and transactions have been eliminated in consolidation.
Basis of Presentation	The preparation of financial statements in conformity with U.S. generally accepted accounting principles ("GAAP") requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities at the date of the financial statements and the reported amount of revenues and expenses during the reporting period. These estimates are based on information available to management at the time the estimates are made. Actual results could differ from those estimates.
Critical Accounting Estimates	Critical Accounting Estimates Critical accounting estimates occur in certain accounting policies and procedures and are particularly susceptible to significant change. Policies that contain critical accounting estimates include the determination of the allowance for loan and lease losses, lease financing and income taxes.
Allowance for Loan and Lease Losses	Allowance for Loan and Lease Losses The allowance for loan and lease losses is maintained at a level appropriate to provide for probable loan and lease losses incurred in the portfolio as of the balance sheet date, including known or anticipated problem loans and leases, as well as for loans and leases which are not currently known to require specific allowances. Loans classified as troubled debt restructuring ("TDR") loans are considered impaired loans. TCF individually evaluates impairment on all impaired commercial and inventory finance loans, certain large impaired equipment finance loans and leases, large consumer real estate TDR loans, auto finance TDR loans and all non-accrual Winthrop Resources Corporation ("Winthrop") leases. All other loans and leases are evaluated collectively for impairment. See Note 6, Allowance for Loan and Lease Losses and Credit Quality Information, for a definition of impaired loans.
	Loan impairment on consumer real estate TDR loans is a key component of the allowance for loan and lease losses. Impairment is generally based upon the present value of the expected future cash flows discounted at the loan's initial effective interest rate, unless the loans are collateral dependent, in which case loan impairment is based upon the fair value of the collateral less selling expenses. See Note 6, Allowance for Loan and Lease Losses and Credit Quality Information, for further information on the determination of the allowance for losses on accruing consumer real estate TDR loans.
	Loan impairment on commercial, equipment finance and inventory finance loans is generally based upon the present value of the expected future cash flows discounted at the loan's initial effective interest rate, unless the loans are collateral dependent, in which case loan impairment is based upon the fair value of collateral less estimated selling costs; however, if payment or satisfaction of the loan is dependent on the operation, rather than the sale of the collateral, the impairment does not include selling costs.
	The impairment for all other loans and leases is evaluated collectively by various characteristics. The collective evaluation of incurred losses in these portfolios is based upon their historical loss rates multiplied by the respective loss emergence period. Factors utilized in the determination of the amount of the allowance include historical trends in loss rates, the portfolio's overall risk characteristics, changes in its character or size, risk rating migration, delinquencies, collateral values and prevailing economic conditions.
	Loans and leases are charged off to the extent they are deemed to be uncollectible. Charge-offs related to confirmed losses are utilized in the historical data in calculating the allowance for loan and lease losses. Consumer real estate loans are charged off to the estimated fair value of underlying collateral, less estimated selling costs, no later than 150 days past due. Additional review of the fair value, less estimated costs to sell, compared with the recorded value occurs upon foreclosure and additional charge-offs are recorded if necessary. Auto finance loans are generally charged off to the estimated fair value of underlying collateral, less estimated selling costs, if repossession is reasonably assured and in process. Otherwise, auto finance loans are charged off in full no later than 120 days past due. Deposit account overdrafts, which are included within other loans, are charged off at or before they are 60 days past due. Commercial loans, leasing and equipment finance loans and inventory finance loans which are considered collateral dependent are charged off to estimated fair value, less estimated selling costs when it becomes probable, based on current information and events, that all principal and interest amounts will not be collectible in accordance with contractual terms. Loans which are not collateral dependent are charged off when deemed uncollectible based on specific facts and circumstances.
	The amount of the allowance for loan and lease losses significantly depends upon management's estimates of variables affecting valuation, appraisals of collateral, evaluations of performance and status and the amounts and timing of future cash flows expected to be received. Such estimates, appraisals, evaluations and cash flows may be subject to frequent adjustments due to changing economic prospects of borrowers, lessees or properties. These estimates are reviewed periodically and adjustments, if necessary, are recorded in the provision for credit losses in the periods in which they become known.
Lease Financing	Lease Financing TCF provides various types of commercial lease financing that are classified for accounting purposes as direct financing, sales-type or operating leases. Leases that transfer substantially all of the benefits and risks of ownership to the lessee are classified as direct financing or sales-type leases and are included in loans and leases. Direct financing and sales-type leases are carried at the combined present value of future minimum lease payments and lease residual values. The determination of lease classification requires various judgments and estimates by management including the fair value of the equipment at lease inception, useful life of the equipment under lease, estimate of the lease residual value and collectability of minimum lease payments.
	Sales-type leases generate dealer profit which is recognized at lease inception by recording lease revenue net of lease cost. Lease revenue consists of the present value of the future minimum lease payments. Lease cost consists of the leased equipment's book value, less the present value of its residual. Interest income on direct financing and sales-type leases is recognized using methods which approximate a level yield over the fixed, non-cancelable term of the lease. TCF receives pro rata rent payments for the interim period until the lease contract commences and the fixed, non-cancelable lease term begins. TCF recognizes these interim payments in the month they are earned and records the income in interest income on direct finance leases. Management has policies and procedures in place for the determination of lease classification and review of the related judgments and estimates for all lease financings.
	Some lease financings include a residual value component, which represents the estimated fair value of the leased equipment at the expiration of the initial term of the transaction. The estimation of residual values involves judgment regarding product and technology changes, customer behavior, shifts in supply and demand and other economic assumptions. TCF reviews residual assumptions on the portfolio at least annually and downward adjustments, if necessary, are charged to non-interest expense in the periods in which they become known.
	TCF occasionally sells minimum lease payments as a credit risk reduction tool to third-party financial institutions at fixed rates on a non-recourse basis with its underlying equipment as collateral. For those transactions which achieve sale treatment, the related lease cash flow stream and the non-recourse financing are derecognized. For those transactions which do not achieve sale treatment, the underlying lease remains on TCF's Consolidated Statements of Financial Condition and non-recourse debt is recorded in the amount of the proceeds received. TCF retains servicing of these leases and bills, collects and remits funds to the third-party financial institution. Upon default by the lessee, the third-party financial institutions may take control of the underlying collateral which TCF would otherwise retain as residual value.
	Leases which do not transfer substantially all benefits and risks of ownership to the lessee are classified as operating leases. Such leased equipment and related initial direct costs are included in other assets on the Consolidated Statements of Financial Condition and depreciated on a straight-line basis over the term of the lease to its estimated salvage value. Depreciation expense is recorded as operating lease expense and included in non-interest expense. Operating lease rental income is recognized when it is due and is reflected as a component of non-interest income. An allowance for lease losses is not provided on operating leases.
Income Taxes	Income Taxes Income taxes are accounted for using the asset and liability method. Under this method, deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax basis carrying amounts. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period in which the enactment date occurs. Also, if current period income tax rates change, the impact on the annual effective income tax rate is applied year-to-date in the period of enactment.
	The determination of current and deferred income taxes is a critical accounting estimate which is based on complex analyses of many factors, including interpretation of income tax laws, the evaluation of uncertain tax positions, differences between the tax and financial reporting bases of assets and liabilities (temporary differences), estimates of amounts due or owed, the timing of reversals of temporary differences and current financial accounting standards. Additionally, there can be no assurance that estimates and interpretations used in determining income tax liabilities will not be challenged by taxing authorities. Actual results could differ significantly from the estimates and tax law interpretations used in determining the current and deferred income tax liabilities.
	In the preparation of income tax returns, tax positions are taken based on interpretation of income tax laws for which the outcome is uncertain. Management periodically reviews and evaluates the status of uncertain tax positions and makes estimates of amounts ultimately due or owed. The benefits of tax positions are recorded in income tax expense in the Consolidated Statements of Income, net of the estimates of ultimate amounts due or owed, including any applicable interest and penalties. Changes in the estimated amounts due or owed may result from closing of the statute of limitations on tax returns, new legislation, clarification of existing legislation through government pronouncements, judicial action and through the examination process. TCF's policy is to report interest and penalties, if any, related to unrecognized tax benefits in income tax expense in the Consolidated Statements of Income.
Investments	Investments Investments are carried at cost. TCF periodically evaluates investments for other than temporary impairment with losses, if any, recorded in non-interest income within gains (losses) on securities, net.
Securities Held to Maturity	Securities Held to Maturity Securities held to maturity are carried at cost and adjusted for amortization of premiums or accretion of discounts using a level yield method; however, transfers of securities available for sale to securities held to maturity are made at fair value at the date of transfer. The unrealized holding gain or loss at the date of each transfer is retained in accumulated other comprehensive income (loss) and in the carrying value of the held to maturity investment security. Such amounts are then amortized over the remaining life of the transferred security as an adjustment of the yield on those securities. TCF periodically evaluates securities held to maturity for other than temporary impairment. Declines in value considered other than temporary, if any, would be recorded as non-interest income within gains (losses) on securities, net.
Securities Available for Sale	Securities Available for Sale Securities available for sale are carried at fair value with the unrealized gains or losses, net of related deferred income taxes, reported within accumulated other comprehensive income (loss), a separate component of equity. The cost of securities sold is determined on a specific identification basis and gains or losses on sales of securities available for sale are recognized on trade dates. TCF evaluates securities available for sale for other than temporary impairment on a quarterly basis. Declines in the value of securities available for sale that are considered other than temporary are recorded in non-interest income within gains (losses) on securities, net. Discounts and premiums on securities available for sale are amortized using a level yield method over the expected life of the security.
Loans and Leases Held for Sale	Loans and Leases Held for Sale Loans and leases designated as held for sale are carried at the lower of cost or fair value. Any amount by which cost exceeds fair value is initially recorded as a valuation allowance and subsequently reflected in the gain or loss on sale when sold. From time to time, management identifies and designates primarily consumer real estate and auto finance loans held in the loan portfolios for sale. These loans are transferred to loans and leases held for sale at the lower of cost or fair market value at the time of transfer. Any associated allowance for loan and lease losses is transferred to the valuation allowance.
Loans and Leases	Loans and Leases Loans and leases are reported at historical cost including net direct fees and costs associated with originating and acquiring loans and leases. The net direct fees and costs for sales-type leases are offset against revenues recorded at the commencement of sales-type leases. Discounts and premiums on acquired loans, net direct fees and costs, unearned discounts and finance charges and unearned lease income are amortized to interest income using methods which approximate a level yield over the estimated remaining lives of the loans and leases. Net direct fees and costs on all lines of credit are amortized on a straight line basis over the contractual life of the line of credit and adjusted for payoffs. Net deferred fees and costs on consumer real estate lines of credit are amortized to service fee income.
Non-accrual Loans and Leases	Non-accrual Loans and Leases Loans and leases are generally placed on non-accrual status when the collection of interest and principal is 90 days or more past due unless, in the case of commercial loans, they are well-secured and in the process of collection. Auto loans are placed on non-accrual status when interest and principal is 120 days past due. Delinquent junior lien loans are also placed on non-accrual status when there is evidence that the related third-party first lien mortgage may be 90 days or more past due.
	Loans on non-accrual status are generally reported as non-accrual loans until there is sustained repayment performance for six consecutive months, with the exception of loans not reaffirmed upon discharge under Chapter 7 bankruptcy, which remain on non-accrual status until TCF expects full repayment of the remaining pre-discharged contractual principal and interest. Income on these loans is recognized on a cash basis when there is sustained repayment performance for six consecutive months, the loan is not more than 60 days delinquent and a current credit evaluation has been completed.
	Generally, when a loan or lease is placed on non-accrual status, uncollected interest accrued in prior years is charged-off against the allowance for loan and lease losses and interest accrued in the current year is reversed against interest income. For non-accrual leases that have been discounted with third-party financial institutions on a non-recourse basis, the related liability is also placed on non-accrual status. Interest payments received on loans and leases in non-accrual status are generally applied to principal unless the remaining principal balance has been determined to be fully collectible, in which case interest income is recognized on a cash basis.
Premises and Equipment	Premises and Equipment Premises and equipment, including leasehold improvements, are carried at cost and are depreciated or amortized on a straight-line basis over estimated useful lives of owned assets and for leasehold improvements over the estimated useful life of the related asset or the lease term, whichever is shorter. Maintenance and repairs are charged to expense as incurred. Rent expense for leased land with facilities is recognized in occupancy and equipment expense. Rent expense for leases with free rent periods or scheduled rent increases is recognized on a straight-line basis over the lease term.
Other Real Estate Owned and Repossessed and Returned Assets	Other Real Estate Owned and Repossessed and Returned Assets Assets acquired through foreclosure, repossession or returned to TCF are initially recorded at the lower of the loan or lease carrying amount or fair value of the collateral less estimated selling costs at the time of transfer to real estate owned or repossessed and returned assets. The fair value of other real estate owned is based on independent appraisals, real estate brokers' price opinions or automated valuation methods, less estimated selling costs. The fair value of repossessed and returned assets is based on available pricing guides, auction results or price opinions, less estimated selling costs. Any carrying amount in excess of the fair value less estimated selling costs is charged off to the allowance for loan and lease losses. Subsequently, if the fair value of an asset, less the estimated costs to sell, declines to less than the carrying amount of the asset, the shortfall is recognized in the period in which it becomes known and is included in foreclosed real estate and repossessed assets, net expense. Operating expenses of properties and recoveries on sales of other real estate owned are also recorded in foreclosed real estate and repossessed assets, net. Operating revenue from foreclosed property is included in other non-interest income.
Investments in Affordable Housing Limited Partnerships	Investments in Affordable Housing Limited Partnerships Investments in affordable housing consist of investments in limited partnerships that operate qualified affordable housing projects or that invest in other limited partnerships formed to operate affordable housing projects. TCF generally utilizes the effective yield method to account for these investments with the tax credits and amortization of the investment reflected in the Consolidated Statements of Income as a reduction of income tax expense. However, depending on circumstances, the equity or cost methods may be utilized. The amount of the investment along with any unfunded equity contributions which are unconditional and legally binding are recorded in other assets. A liability for the unfunded equity contributions is recorded in other liabilities.
Interest-Only Strips	Interest-Only Strips TCF periodically sells loans to third party financial institutions at fixed or variable rates. For those transactions which achieve sale treatment, the underlying loan is not recognized on TCF's Consolidated Statements of Financial Condition. The Company sells these loans at par value and generally retains an interest in the future cash flows of borrower loan payments, known as an interest-only strip. The interest-only strip is recorded at fair value at the time of sale. The fair value of the interest-only strip represents the present value of future cash flows generated by the loans to be retained by TCF. After initial recording of the interest-only strip, the accretable yield is measured as the difference between the initial investment, or fair value, and the cash flows expected to be collected. The accretable yield is amortized into interest income over the life of the interest-only strip using the effective yield method. The expected cash flows are evaluated quarterly to determine if they have changed from previous projections. If the present value of the original cash flows expected to be collected is less than the present value of the current estimate of cash flows to be collected, the change is adjusted prospectively over the remaining life of the interest-only strip. If the present value of the original cash flows expected to be collected is greater than the present value of the current estimate, an other than temporary impairment is generally recorded.
Intangible Assets	Intangible Assets All assets and liabilities acquired in purchase acquisitions, including goodwill and other intangibles, are recorded at fair value. Goodwill is recorded when the purchase price of an acquisition is greater than the fair value of net assets, including identifiable intangible assets. Goodwill is not amortized, but assessed for impairment on an annual basis at the reporting unit level. Interim impairment analysis may be required if events occur or circumstances change that would more likely than not reduce a reporting unit's fair value below its carrying amount. Other intangible assets are amortized on a straight-line or effective yield basis over their estimated useful lives and are subject to impairment if events or circumstances indicate a possible inability to realize their carrying amounts.
	When testing for goodwill impairment, TCF initially performs a qualitative assessment. Based on the results of this qualitative assessment, if TCF concludes it is more likely than not that a reporting unit's fair value is less than its carrying amount, a quantitative analysis is performed. Quantitative valuation methodologies primarily include discounted cash flow analysis in determining fair value of reporting units. If the fair value is less than the carrying amount, additional analysis is required to measure the amount of impairment. Impairment losses, if any, are recorded as a charge to non-interest expense and an adjustment to the carrying value of goodwill.
	Other intangible assets are reviewed for impairment whenever events or changes in circumstances indicate their carrying amount may not be recoverable. Impairment is indicated if the sum of the undiscounted estimated future net cash flows is less than the carrying value of the intangible asset. Impairment losses, if any, permanently reduce the carrying value of the other intangible assets.
Stock-Based Compensation	Stock-Based Compensation The fair value of restricted stock and stock options is determined on the date of grant and amortized to compensation expense, with a corresponding increase in additional paid-in capital, over the longer of the service period or performance period, but in no event beyond an employee's retirement date or date of employment termination. For performance-based restricted stock, TCF estimates the degree to which performance conditions will be met to determine the number of shares that will vest and the related compensation expense. Compensation expense is adjusted in the period such estimates change. Non-forfeitable dividends, if any, paid on shares of restricted stock are recorded to retained earnings for shares that are expected to vest and to compensation expense for shares that are not expected to vest.
	Income tax benefits related to stock compensation, in excess of grant date fair value less any proceeds on exercise, are recognized as additional paid-in capital upon vesting or exercise and delivery of the stock. Any income tax benefits that are less than grant date fair value less any proceeds on exercise are recognized as a reduction of additional paid in capital to the extent of previously recognized income tax benefits and then as income tax expense for any remaining amount. See Note 15, Stock Compensation, for additional information concerning stock-based compensation.
Deposit Account Overdrafts	Deposit Account Overdrafts Deposit account overdrafts are reported in other loans and leases. Net losses on uncollectible overdrafts are reported as net charge-offs in the allowance for loan and lease losses within 60 days from the date of overdraft. Uncollectible deposit fees are reversed against fees and service charges and a related reserve for uncollectible deposit fees is maintained in other liabilities. Other deposit account losses are reported in other non-interest expense.

Investments_Tables

Investments (Tables)	12 Months Ended
	Dec. 31, 2014
Investments
Carrying values of investments	Investments consisted of the following.
		At December 31,
	(In thousands)	2014		2013
	Federal Home Loan Bank stock, at cost	$	47,914	$	56,845
	Federal Reserve Bank stock, at cost	37,578		37,481
	Total investments	$	85,492	$	94,326

Securities_Available_for_Sale_1

Securities Available for Sale and Securities Held to Maturity (Tables)	12 Months Ended
	Dec. 31, 2014
Investments, Debt and Equity Securities [Abstract]
Schedule of securities	Securities consisted of the following.
		At December 31,
		2014											2013
	(Dollars in thousands)	Amortized			Gross		Gross			Fair			Amortized				Gross		Gross		Fair
		Cost			Unrealized		Unrealized			Value			Cost				Unrealized		Unrealized		Value
					Gains		Losses										Gains		Losses
	Securities available for sale:
	Mortgage-backed securities:
	U.S. Government sponsored enterprises and federal agencies	$	461,575		$	2,405	$	741		$	463,239		$	592,283			$	1,131	$	45,377	$	548,037
	Other	55			—		—			55			93				—		—		93
	Other securities	—			—		—			—			1,642				1,292		—		2,934
	Total securities available for sale	$	461,630		$	2,405	$	741		$	463,294		$	594,018			$	2,423	$	45,377	$	551,064
	Weighted-average yield	2.62		%									2.65		%
	Securities held to maturity:
	Mortgage-backed securities:
	U.S. Government sponsored enterprises and federal agencies	$	209,538		$	7,988	$	109		$	217,417		$	14,610			$	—	$	—	$	14,610
	Other securities	4,916			—		—			4,916			5,302				—		—		5,302
	Total securities held to maturity	$	214,454		$	7,988	$	109		$	222,333		$	19,912			$	—	$	—	$	19,912
	Weighted-average yield	2.64		%									3.43		%
Schedule of gross unrealized losses and fair value of securities available for sale and securities held to maturity that are in a loss position	The following tables show the gross unrealized losses and fair value of securities available for sale at December 31, 2014 and 2013 and securities held to maturity at December 31, 2014, aggregated by investment category and the length of time the securities were in a continuous loss position. There were no gross unrealized losses for securities held to maturity at December 31, 2013.
		At December 31, 2014
		Less than 12 months					12 months or more						Total
	(In thousands)	Fair Value			Unrealized		Fair Value			Unrealized			Fair Value				Unrealized
					Losses					Losses							Losses
	Securities available for sale:
	Mortgage-backed securities:
	U.S. Government sponsored enterprises and federal agencies	$	—		$	—	$	198,550		$	741		$	198,550			$	741
	Total securities available for sale	$	—		$	—	$	198,550		$	741		$	198,550			$	741
	Securities held to maturity:
	Mortgage-backed securities:
	U.S. Government sponsored enterprises and federal agencies	$	2,602		$	109	$	—		$	—		$	2,602			$	109
	Total securities held to maturity	$	2,602		$	109	$	—		$	—		$	2,602			$	109
		At December 31, 2013
		Less than 12 months					12 months or more						Total
	(In thousands)	Fair Value			Unrealized		Fair Value			Unrealized			Fair Value				Unrealized
					Losses					Losses							Losses
	Securities available for sale:
	Mortgage-backed securities:
	U.S. Government sponsored enterprises and federal agencies	$	353,449		$	22,678	$	156,472		$	22,699		$	509,921			$	45,377
	Total securities available for sale	$	353,449		$	22,678	$	156,472		$	22,699		$	509,921			$	45,377
Schedule of amortized cost, fair value and yield of securities available for sale and securities held to maturity by contractual maturity	The amortized cost, fair value and yield of securities available for sale and securities held to maturity by contractual maturity at December 31, 2014 and 2013, are shown below. The remaining contractual principal maturities do not consider possible prepayments. Remaining expected maturities will differ from contractual maturities because borrowers may have the right to prepay.
		At December 31,
		2014							2013
	(Dollars in thousands)	Amortized Cost			Fair Value		Yield		Amortized Cost			Fair Value				Yield
	Securities available for sale:
	Due in one year or less	$	4		$	4	11.63	%	$	—		$	—			—	%
	Due in 1-5 years	76			76		4.53		138			140				5.24
	Due in 5-10 years	86,806			87,594		1.93		24,328			24,543				2.17
	Due after 10 years	374,744			375,620		2.78		567,910			523,447				2.67
	No stated maturity	—			—		—		1,642			2,934				—
	Total securities available for sale	$	461,630		$	463,294	2.62		$	594,018		$	551,064			2.65
	Securities held to maturity:
	Due in one year or less	$	500		$	500	2	%	$	—		$	—			—	%
	Due in 1-5 years	2,500			2,500		3.08		3,000			3,000				2.9
	Due in 5-10 years	400			400		3		—			—				—
	Due after 10 years	211,054			218,933		2.64		16,912			16,912				3.52
	Total securities held to maturity	$	214,454		$	222,333	2.64		$	19,912		$	19,912			3.43

Loans_and_Leases_Tables

Loans and Leases (Tables)	12 Months Ended
	Dec. 31, 2014
Receivables [Abstract]
Information about loans and leases	Loans and leases consisted of the following.
		At December 31,				Percent Change
	(Dollars in thousands)	2014		2013
	Consumer real estate:
	First mortgage lien	$	3,139,152	$	3,766,421	(16.7	)%
	Junior lien	2,543,212		2,572,905		(1.2	)
	Total consumer real estate	5,682,364		6,339,326		(10.4	)
	Commercial:
	Commercial real estate:
	Permanent	2,382,144		2,604,673		(8.5	)
	Construction and development	242,111		139,024		74.2
	Total commercial real estate	2,624,255		2,743,697		(4.4	)
	Commercial business	533,410		404,655		31.8
	Total commercial	3,157,665		3,148,352		0.3
	Leasing and equipment finance	3,745,322		3,428,755		9.2
	Inventory finance	1,877,090		1,664,377		12.8
	Auto finance	1,915,061		1,239,386		54.5
	Other	24,144		26,743		(9.7	)
	Total loans and leases(1)	$	16,401,646	$	15,846,939	3.5
	-1	Loans and leases are reported at historical cost including net direct fees and costs associated with originating and acquiring loans and leases, lease residuals, unearned income and unamortized purchase premiums and discounts. The aggregate amount of these loan and lease adjustments was $43.4 million and $30.3 million at December 31, 2014 and 2013, respectively.
Future minimum lease payments receivable	Future minimum lease payments receivable for direct financing, sales-type leases and operating leases as of December 31, 2014 are as follows:
	(In thousands)
	2015	$	711,813
	2016	529,282
	2017	365,547
	2018	213,241
	2019	105,650
	Thereafter	36,949
	Total	$	1,962,482

Allowance_for_Loan_and_Lease_L1

Allowance for Loan and Lease Losses and Credit Quality Information (Tables)	12 Months Ended
	Dec. 31, 2014
Allowance for Loan and Lease Losses and Credit Quality Information
Allowance for loan and lease losses and other information	The following tables provide the allowance for loan and lease losses and other information regarding the allowance for loan and lease losses. TCF's key credit quality indicator is the receivable's payment performance status, defined as accruing or non-accruing.
	(In thousands)	Consumer			Commercial			Leasing and			Inventory			Auto			Other			Total
		Real Estate						Equipment			Finance			Finance
								Finance
	At or For the Year Ended December 31, 2014:
	Balance, beginning of period	$	176,030		$	37,467		$	18,733		$	8,592		$	10,623		$	785		$	252,230
	Charge-offs	(63,126		)	(8,657		)	(7,316		)	(1,653		)	(11,856		)	(8,359		)	(100,967		)
	Recoveries	6,867			2,887			3,705			826			1,491			5,860			21,636
	Net charge-offs	(56,259		)	(5,770		)	(3,611		)	(827		)	(10,365		)	(2,499		)	(79,331		)
	Provision for credit losses	63,973			(259		)	3,324			2,498			23,742			2,459			95,737
	Other(1)	(98,383		)	(71		)	—			(243		)	(5,770		)	—			(104,467		)
	Balance, end of period	$	85,361		$	31,367		$	18,446		$	10,020		$	18,230		$	745		$	164,169
	At or For the Year Ended December 31, 2013:
	Balance, beginning of period	$	182,013		$	51,575		$	21,037		$	7,569		$	4,136		$	798		$	267,128
	Charge-offs	(97,508		)	(28,944		)	(7,277		)	(1,141		)	(5,305		)	(9,115		)	(149,290		)
	Recoveries	8,644			2,770			3,968			373			607			6,518			22,880
	Net charge-offs	(88,864		)	(26,174		)	(3,309		)	(768		)	(4,698		)	(2,597		)	(126,410		)
	Provision for credit losses	87,100			12,515			1,005			1,949			13,215			2,584			118,368
	Other	(4,219		)	(449		)	—			(158		)	(2,030		)	—			(6,856		)
	Balance, end of period	$	176,030		$	37,467		$	18,733		$	8,592		$	10,623		$	785		$	252,230
	-1	Included in Other for consumer real estate is the transfer of $95.3 million, comprised of $77.0 million of previously established allowance for loan and lease losses and an additional $18.3 million of write-downs arising from the transfer to loans held for sale in conjunction with the portfolio sale of consumer real estate TDR loans.
Allowance for loan and lease losses and balances by type of allowance methodology	The following tables provide information regarding the allowance for loan and lease losses and balances by type of allowance methodology.
		At December 31, 2014
	(In thousands)	Consumer			Commercial			Leasing and			Inventory			Auto			Other			Total
		Real Estate						Equipment			Finance			Finance
								Finance
	Allowance for loan and lease losses:
	Collectively evaluated for impairment	$	57,167		$	27,594		$	16,310		$	9,627		$	17,046		$	741		$	128,485
	Individually evaluated for impairment	28,194			3,773			2,136			393			1,184			4			35,684
	Total	$	85,361		$	31,367		$	18,446		$	10,020		$	18,230		$	745		$	164,169
	Loans and leases outstanding:
	Collectively evaluated for impairment	$	5,462,005		$	3,038,378		$	3,731,420		$	1,874,481		$	1,911,267		$	24,055		$	16,041,606
	Individually evaluated for impairment	220,359			119,287			13,763			2,609			3,676			89			359,783
	Loans acquired with deteriorated credit quality	—			—			139			—			118			—			257
	Total	$	5,682,364		$	3,157,665		$	3,745,322		$	1,877,090		$	1,915,061		$	24,144		$	16,401,646
		At December 31, 2013
	(In thousands)	Consumer			Commercial			Leasing and			Inventory			Auto			Other			Total
		Real Estate						Equipment			Finance			Finance
								Finance
	Allowance for loan and lease losses:
	Collectively evaluated for impairment	$	54,449		$	28,994		$	17,093		$	8,308		$	10,528		$	781		$	120,153
	Individually evaluated for impairment	121,581			8,473			1,640			284			95			4			132,077
	Total	$	176,030		$	37,467		$	18,733		$	8,592		$	10,623		$	785		$	252,230
	Loans and leases outstanding:
	Collectively evaluated for impairment	$	5,673,518		$	2,971,308		$	3,412,769		$	1,657,636		$	1,238,556		$	26,649		$	14,980,436
	Individually evaluated for impairment	665,808			177,044			15,139			6,741			470			94			865,296
	Loans acquired with deteriorated credit quality	—			—			847			—			360			—			1,207
	Total	$	6,339,326		$	3,148,352		$	3,428,755		$	1,664,377		$	1,239,386		$	26,743		$	15,846,939
Information regarding accruing and non-accruing loans and leases	The following tables set forth information regarding TCF's accruing and non-accrual loans and leases. Non-accrual loans and leases are those which management believes have a higher risk of loss. Delinquent balances are determined based on the contractual terms of the loan or lease.
		At December 31, 2014
	(In thousands)	Current-59 Days			60-89 Days			90 Days or More			Total			Non-accrual			Total
		Delinquent and			Delinquent			Delinquent and			Accruing
		Accruing			and Accruing			Accruing
	Consumer real estate:
	First mortgage lien	$	2,987,992		$	13,176		$	194		$	3,001,362		$	137,790		$	3,139,152
	Junior lien	2,505,640			2,091			—			2,507,731			35,481			2,543,212
	Total consumer real estate	5,493,632			15,267			194			5,509,093			173,271			5,682,364
	Commercial:
	Commercial real estate	2,599,701			—			—			2,599,701			24,554			2,624,255
	Commercial business	532,929			—			—			532,929			481			533,410
	Total commercial	3,132,630			—			—			3,132,630			25,035			3,157,665
	Leasing and equipment finance	3,728,115			2,242			307			3,730,664			12,670			3,743,334
	Inventory finance	1,874,933			49			26			1,875,008			2,082			1,877,090
	Auto finance	1,907,005			2,785			1,478			1,911,268			3,676			1,914,944
	Other	24,144			—			—			24,144			—			24,144
	Subtotal	16,160,459			20,343			2,005			16,182,807			216,734			16,399,541
	Portfolios acquired with deteriorated credit quality	2,017			83			5			2,105			—			2,105
	Total	$	16,162,476		$	20,426		$	2,010		$	16,184,912		$	216,734		$	16,401,646
		At December 31, 2013
	(In thousands)	Current-59 Days			60-89 Days			90 Days or More			Total			Non-accrual			Total
		Delinquent and			Delinquent			Delinquent and			Accruing
		Accruing			and Accruing			Accruing
	Consumer real estate:
	First mortgage lien	$	3,564,716		$	19,815		$	1,079		$	3,585,610		$	180,811		$	3,766,421
	Junior lien	2,531,151			3,532			—			2,534,683			38,222			2,572,905
	Total consumer real estate	6,095,867			23,347			1,079			6,120,293			219,033			6,339,326
	Commercial:
	Commercial real estate	2,706,633			886			—			2,707,519			36,178			2,743,697
	Commercial business	399,750			190			354			400,294			4,361			404,655
	Total commercial	3,106,383			1,076			354			3,107,813			40,539			3,148,352
	Leasing and equipment finance	3,404,346			2,226			613			3,407,185			14,041			3,421,226
	Inventory finance	1,661,798			29			21			1,661,848			2,529			1,664,377
	Auto finance	1,236,678			1,105			773			1,238,556			470			1,239,026
	Other	26,323			9			1			26,333			410			26,743
	Subtotal	15,531,395			27,792			2,841			15,562,028			277,022			15,839,050
	Portfolios acquired with deteriorated credit quality	7,870			14			5			7,889			—			7,889
	Total	$	15,539,265		$	27,806		$	2,846		$	15,569,917		$	277,022		$	15,846,939
Interest income recognized on loans and leases in non-accrual status and contractual interest	The following table provides interest income recognized on loans and leases in non-accrual status and contractual interest that would have been recorded had the loans and leases performed in accordance with their original contractual terms.
		Year Ended December 31,
	(In thousands)	2014			2013			2012
	Contractual interest due on non-accrual loans and leases	$	26,584		$	33,046		$	39,232
	Interest income recognized on non-accrual loans and leases	9,359			12,149			9,401
	Foregone interest income	$	17,225		$	20,897		$	29,831
Summary of consumer real estate loans to customers in bankruptcy	The following table provides information regarding consumer real estate loans to customers currently involved in ongoing Chapter 7 or Chapter 13 bankruptcy proceedings which have not yet been discharged.
		At December 31,
	(In thousands)	2014			2013
	Consumer real estate loans to customers in bankruptcy:
	0-59 days delinquent and accruing	$	47,731		$	65,321
	60+ days delinquent and accruing	247			682
	Non-accrual	12,284			13,475
	Total consumer real estate loans to customers in bankruptcy	$	60,262		$	79,478
Schedule of accruing loans that were restructured within 12 months and defaulted	The table below summarizes TDR loans that defaulted during the years ended December 31, 2014 and 2013, which were modified during the respective reporting period or within one year of the beginning of the respective reporting period. TCF considers a loan to have defaulted when it becomes 90 or more days delinquent under the modified terms, has been transferred to non-accrual status subsequent to the modification or has been transferred to other real estate owned or repossessed and returned assets.
		Loan Balance(1)
		Year Ended December 31,
	(Dollars in thousands)	2014			2013
	Consumer real estate:
	First mortgage lien	$	1,969		$	12,510
	Junior lien	1,364			2,479
	Total consumer real estate	3,333			14,989
	Commercial:
	Commercial real estate	3,895			5,561
	Commercial business	127			—
	Total commercial	4,022			5,561
	Leasing and equipment finance	—			268
	Auto finance	392			59
	Other	—			1
	Defaulted TDR loans modified during the applicable period	$	7,747		$	20,878
	Total loans modified in the applicable period	$	177,674		$	374,761
	Defaulted modified TDR loans as a percent of total loans modified in the applicable period	4.4		%	5.6		%
	-1	The loan balances presented are not materially different than the pre-modification loan balances as TCF's loan modifications generally do not forgive principal amounts.
Impaired loans included in previous amounts disclosed within performing and non-accrual loans and leases and loan modifications for borrowers with financial difficulties	The following table summarizes impaired loans.
		At December 31,
		2014									2013
	(In thousands)	Unpaid			Loan			Related			Unpaid Contractual Balance			Loan			Related Allowance Recorded
		Contractual			Balance			Allowance						Balance
		Balance						Recorded
	Impaired loans with an allowance recorded:
	Consumer real estate:
	First mortgage lien	$	114,526		$	101,668		$	18,140		$	553,736		$	521,248		$	107,841
	Junior lien	65,413			55,405			9,427			85,309			72,548			12,989
	Total consumer real estate	179,939			157,073			27,567			639,045			593,796			120,830
	Commercial:
	Commercial real estate	58,157			54,412			3,772			84,851			71,785			7,594
	Commercial business	18			18			1			9,917			4,380			880
	Total commercial	58,175			54,430			3,773			94,768			76,165			8,474
	Leasing and equipment finance	8,257			8,257			1,457			8,238			8,238			717
	Inventory finance	1,754			1,758			393			6,741			6,741			284
	Auto finance	3,074			2,928			1,184			373			308			95
	Other	92			89			4			97			94			4
	Total impaired loans with an allowance recorded	251,291			224,535			34,378			749,262			685,342			130,404
	Impaired loans without an allowance recorded:
	Consumer real estate:
	First mortgage lien	53,606			35,147			—			59,233			43,025			—
	Junior lien	33,796			7,398			—			26,710			4,306			—
	Total consumer real estate	87,402			42,545			—			85,943			47,331			—
	Commercial:
	Commercial real estate	57,809			50,500			—			102,523			79,833			—
	Commercial business	482			480			—			5,410			5,412			—
	Total commercial	58,291			50,980			—			107,933			85,245			—
	Inventory finance	848			851			—			—			—			—
	Auto finance	1,484			748			—			317			162			—
	Total impaired loans without an allowance recorded	148,025			95,124			—			194,193			132,738			—
	Total impaired loans	$	399,316		$	319,659		$	34,378		$	943,455		$	818,080		$	130,404
Average balance of impaired loans and interest income recognized on impaired loans	The average loan balance of impaired loans and interest income recognized on impaired loans during the years ended December 31, 2014 and 2013 are included within the table below.
		Year Ended December 31,
		2014						2013
	(In thousands)	Average Loan Balance			Interest Income Recognized			Average Loan Balance			Interest Income Recognized
	Impaired loans with an allowance recorded:
	Consumer real estate:
	First mortgage lien	$	311,458		$	14,715		$	481,292		$	17,263
	Junior lien	63,977			3,492			57,692			3,762
	Total consumer real estate	375,435			18,207			538,984			21,025
	Commercial:
	Commercial real estate	63,099			2,349			99,177			3,193
	Commercial business	2,199			—			10,060			70
	Total commercial	65,298			2,349			109,237			3,263
	Leasing and equipment finance	8,247			58			7,954			174
	Inventory finance	4,249			97			4,114			158
	Auto finance	1,617			—			154			2
	Other	92			7			66			6
	Total impaired loans with an allowance recorded	454,938			20,718			660,509			24,628
	Impaired loans without an allowance recorded:
	Consumer real estate:
	First mortgage lien	39,086			2,321			92,268			2,305
	Junior lien	5,852			1,285			15,236			1,682
	Total consumer real estate	44,938			3,606			107,504			3,987
	Commercial:
	Commercial real estate	65,167			2,973			101,921			3,165
	Commercial business	2,946			94			5,674			215
	Total commercial	68,113			3,067			107,595			3,380
	Inventory finance	426			126			—			—
	Auto finance	455			—			132			—
	Total impaired loans without an allowance recorded	113,932			6,799			215,231			7,367
	Total impaired loans	$	568,870		$	27,517		$	875,740		$	31,995

Premises_and_Equipment_Tables

Premises and Equipment (Tables)	12 Months Ended
	Dec. 31, 2014
Property, Plant and Equipment [Abstract]
Schedule of premises and equipment	Premises and equipment consisted of the following.
		At December 31,
	(In thousands)	2014		2013
	Land	$	152,418	$	154,136
	Office buildings	276,943		277,085
	Leasehold improvements	53,954		54,069
	Furniture and equipment	312,628		294,387
	Subtotal	795,943		779,677
	Less: Accumulated depreciation and amortization	359,582		342,075
	Total	$	436,361	$	437,602
Schedule of future minimum rental payments for operating leases	At December 31, 2014, the total future minimum rental payments for operating leases of premises and equipment are as follows.
	(In thousands)
	2015	$	26,894
	2016	29,592
	2017	28,201
	2018	26,355
	2019	15,199
	Thereafter	67,030
	Total	$	193,271

Goodwill_and_Other_Intangible_1

Goodwill and Other Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2014
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of goodwill and other intangible assets	Goodwill and other intangible assets consisted of the following.
		At December 31,
		2014						2013
	(In thousands)	Gross		Accumulated		Net		Gross		Accumulated		Net
		Amount		Amortization		Amount		Amount		Amortization		Amount
	Amortizable intangible assets:
	Deposit base intangibles	$	3,049	$	1,502	$	1,547	$	3,049	$	1,105	$	1,944
	Customer base intangibles	2,730		1,377		1,353		2,730		996		1,734
	Non-compete agreement	4,590		2,849		1,741		4,590		1,942		2,648
	Tradename	300		300		—		300		300		—
	Total	$	10,669	$	6,028	$	4,641	$	10,669	$	4,343	$	6,326
	Unamortizable intangible assets:
	Goodwill related to funding segment	$	141,245			$	141,245	$	141,245			$	141,245
	Goodwill related to lending segment	84,395				84,395		84,395				84,395
	Total	$	225,640			$	225,640	$	225,640			$	225,640

Deposits_Tables

Deposits (Tables)	12 Months Ended
	Dec. 31, 2014
Deposits [Abstract]
Summary of deposits	Deposits consisted of the following.
		At December 31,
		2014								2013
	(Dollars in thousands)	Weighted-Average Rate		Amount			% of			Weighted-Average Rate		Amount		% of
							Total							Total
	Checking:
	Non-interest bearing	—	%	$	2,832,526		18.3	%		—	%	$	2,642,600	18.3	%
	Interest bearing	0.04		2,362,717			15.3			0.06		2,337,851		16.2
	Total checking	0.02		5,195,243			33.6			0.03		4,980,451		34.5
	Savings	0.15		5,212,320			33.7			0.2		6,194,003		42.9
	Money market	0.54		1,993,130			13			0.29		831,910		5.8
	Total checking, savings and money market	0.13		12,400,693			80.3			0.14		12,006,364		83.2
	Certificates of deposit	0.78		3,049,189			19.7			0.86		2,426,412		16.8
	Total deposits	0.26		$	15,449,882		100	%		0.26		$	14,432,776	100	%
Schedule of certificates of deposit remaining maturities	Certificates of deposit had the following remaining maturities at December 31, 2014.
	(In thousands)	Denominations			Denominations			Total
		$100 Thousand or			Less Than
		Greater			$100 Thousand
	Maturity:
	0-3 months	$	250,200		$	348,379		$	598,579
	4-6 months	150,195			244,631			394,826
	7-12 months	345,161			491,403			836,564
	13-24 months	505,991			587,088			1,093,079
	Over 24 months	75,609			50,532			126,141
	Total	$	1,327,156		$	1,722,033		$	3,049,189

Shortterm_Borrowings_Tables

Short-term Borrowings (Tables)	12 Months Ended
	Dec. 31, 2014
Debt Disclosure [Abstract]
Schedule of selected information for short-term borrowings (borrowings with an original maturity of less than one year)	Selected information for short-term borrowings (borrowings with an original maturity of less than one year) consisted of the following.
		At December 31,
		2014				2013
	(Dollars in thousands)	Amount		Rate		Amount		Rate
	Period end balance:
	Securities sold under repurchase agreements	$	4,425	0.1	%	$	4,918	0.1	%
	Total	$	4,425	0.1		$	4,918	0.1
	Average daily balances for the period ended:
	Federal Home Loan Bank advances	$	74,385	0.26	%	$	14	0.34	%
	Federal funds purchased	375		0.4		660		0.34
	Securities sold under repurchase agreements	5,956		0.18		5,713		0.18
	Line of Credit - TCF Commercial Finance Canada, Inc.	2,957		1.88		1,298		2.57
	Total	$	83,673	0.31		$	7,685	0.6
	Maximum month-end balances for the period ended:
	Federal Home Loan Bank advances	$	250,000	N.A.		$	—	N.A.
	Securities sold under repurchase agreements	4,425		N.A.		7,071		N.A.
	Line of Credit - TCF Commercial Finance Canada, Inc.	11,751		N.A.		9,587		N.A.
	N.A. Not Applicable.

Longterm_Borrowings_Tables

Long-term Borrowings (Tables)	12 Months Ended
	Dec. 31, 2014
Debt Disclosure [Abstract]
Information about long-term borrowings	Long-term borrowings consisted of the following.
			At December 31,
			2014				2013
	(Dollars in thousands)	Stated	Amount		Weighted-		Amount		Weighted-
		Maturity			Average Rate				Average Rate
	Federal Home Loan Bank advances	2014	$	—	—	%	$	398,000	0.37	%
		2015	125,000		0.38		200,000		0.33
		2016	547,000		0.75		497,000		0.76
		2017	275,000		0.25		75,000		0.21
	Subtotal		947,000		0.56		1,170,000		0.52
	Subordinated bank notes	2015	—		—		50,000		1.83
		2016	74,930		5.59		74,868		5.59
		2022	109,194		6.37		109,113		6.37
	Subtotal		184,124		6.05		233,981		5.15
	Discounted lease rentals	2014	—		—		26,275		4.06
		2015	32,904		3.84		18,866		3.96
		2016	27,539		3.83		13,319		3.92
		2017	20,580		3.82		8,281		3.69
		2018	9,032		3.92		1,689		3.45
		2019	2,589		4.23		76		3.31
		2020	160		4.57		—		—
		2021	83		4.57		—		—
	Subtotal		92,887		3.85		68,506		3.94
	Other long-term	2014	—		—		2,718		1.36
		2015	2,670		1.36		2,669		1.36
		2016	2,642		1.36		2,705		1.36
		2017	2,742		1.36		2,746		1.36
	Subtotal		8,054		1.36		10,838		1.36
	Total long-term borrowings		$	1,232,065	1.63		$	1,483,325	1.41

Income_Taxes_Tables

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Schedule of components of provision for income taxes	The following table summarizes applicable income taxes in the Consolidated Statements of Income.
	(In thousands)	Current				Deferred				Total
	Year ended December 31, 2014:
	Federal	$	55,062			$	26,308			$	81,370
	State	2,087				11,147				13,234
	Foreign	5,185				(23		)		5,162
	Total	$	62,334			$	37,432			$	99,766
	Year ended December 31, 2013:
	Federal	$	(38,206	)		$	107,630			$	69,424
	State	7,686				3,941				11,627
	Foreign	3,939				(645		)		3,294
	Total	$	(26,581	)		$	110,926			$	84,345
	Year ended December 31, 2012:
	Federal	$	6,646			$	(129,082	)		$	(122,436	)
	State	7,994				(18,416		)		(10,422		)
	Total	$	14,640			$	(147,498	)		$	(132,858	)
Schedule of effective income tax rate that differed from the statutory federal income tax rate	TCF's effective income tax rate differed from the statutory federal income tax rate of 35.0% as a result of the following.
		Year Ended December 31,
		2014			2013			2012
	Federal income tax rate	35	%		35	%		35	%
	Increase (decrease) resulting from:
	State income tax, net of federal income tax	3.06			3.11			1.99
	Non-controlling interest tax effect	(0.92	)		(1.01	)		0.64
	Tax exempt income	(0.76	)		(0.86	)		0.55
	Foreign tax effects	(0.58	)		(1.13	)		—
	Deferred tax adjustments	(0.33	)		(0.30	)		1.4
	Civil money penalty	—			—			(1.03	)
	Other, net	(0.01	)		(0.11	)		0.58
	Effective income tax rate	35.46	%		34.7	%		39.13	%
Schedule of reconciliation of the changes in unrecognized tax benefits	A reconciliation of the changes in unrecognized tax benefits is as follows.
		At or For the Year Ended December 31,
	(In thousands)	2014				2013				2012
	Balance, beginning of period	$	4,704			$	4,230			$	2,377
	Increases for tax positions related to the current year	468				394				449
	Increases for tax positions related to prior years	8				362				1,781
	Decreases for tax positions related to prior years	(350		)		(67		)		—
	Settlements with taxing authorities	—				(39		)		(70		)
	Decreases related to lapses of applicable statutes of limitation	(181		)		(176		)		(307		)
	Balance, end of period	$	4,649			$	4,704			$	4,230
Schedule of significant components of the Company's deferred tax assets and deferred tax liabilities	The significant components of the Company's deferred tax assets and deferred tax liabilities were as follows.
		At December 31,
	(In thousands)	2014				2013
	Deferred tax assets:
	Allowance for loan and lease losses	$	63,862			$	62,464
	Stock compensation and deferred compensation plans	34,850				29,576
	Net operating losses and credit carryforwards	11,649				48,692
	Valuation allowance	(5,669		)		(8,745		)
	Non-accrual interest	9,333				1,911
	Securities available for sale	5,397				16,301
	Accrued expense	4,892				5,203
	Other	2,721				6,676
	Total deferred tax assets	127,035				162,078
	Deferred tax liabilities:
	Lease financing	299,621				284,767
	Premises and equipment	19,114				19,289
	Loan fees and discounts	14,921				17,287
	Prepaid expenses	12,479				10,526
	Goodwill and other intangibles	4,139				4,694
	Other	8,106				7,361
	Total deferred tax liabilities	358,380				343,924
	Net deferred tax liabilities	$	231,345			$	181,846

Equity_Tables

Equity (Tables)	12 Months Ended
	Dec. 31, 2014
Equity [Abstract]
Treasury stock and other	Treasury stock and other consisted of the following.
		At December 31,
	(In thousands)	2014			2013
	Treasury stock, at cost	$	(1,102	)	$	(1,102	)
	Shares held in trust for deferred compensation plans, at cost	(48,298		)	(41,096		)
	Total	$	(49,400	)	$	(42,198	)

Regulatory_Capital_Requirement1

Regulatory Capital Requirements (Tables)	12 Months Ended
	Dec. 31, 2014
Regulatory Capital Requirements [Abstract]
Schedule of regulatory capital information for TCF and TCF Bank	The following table presents regulatory capital information for TCF and TCF Bank.
		Actual				Minimum				Well-Capitalized
						Capital Requirement(1)				Capital Requirement(1)
	(Dollars in thousands)	Amount		Ratio		Amount		Ratio		Amount		Ratio
	At December 31, 2014:
	Tier 1 leverage capital:(2)
	TCF	$	1,919,887	10.07	%	$	762,711	4	%	N.A.		N.A.
	TCF Bank	1,836,019		9.63		762,746		4		$	953,432	5	%
	Tier 1 risk-based capital:
	TCF	1,919,887		11.76		652,857		4		979,286		6
	TCF Bank	1,836,019		11.25		652,785		4		979,177		6
	Total risk-based capital:
	TCF	2,209,999		13.54		1,305,714		8		1,632,143		10
	TCF Bank	2,126,131		13.03		1,305,569		8		1,631,961		10
	At December 31, 2013:
	Tier 1 leverage capital:(2)
	TCF	$	1,763,682	9.71	%	$	726,242	4	%	N.A.		N.A.
	TCF Bank	1,675,082		9.23		725,895		4		$	907,368	5	%
	Tier 1 risk-based capital:
	TCF	1,763,682		11.41		618,228		4		927,342		6
	TCF Bank	1,675,082		10.84		618,033		4		927,049		6
	Total risk-based capital:
	TCF	2,107,981		13.64		1,236,456		8		1,545,571		10
	TCF Bank	2,018,959		13.07		1,236,066		8		1,545,082		10
	N.A. Not Applicable.
	-1	The minimum and well-capitalized requirements are determined by the Federal Reserve Board for TCF and by the OCC for TCF Bank pursuant to the Federal Deposit Insurance Corporation Improvement Act of 1991.
	-2	The minimum Tier 1 leverage ratio for bank holding companies and banks is 3.0 or 4.0 percent, depending on factors specified in regulations issued by federal banking agencies.

Stock_Compensation_Tables

Stock Compensation (Tables)	12 Months Ended
	Dec. 31, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Information about restricted stock	Information about restricted stock is summarized as follows.
		At or For the Year Ended December 31,
	(Dollars in thousands)	2014				2013			2012
	Compensation expense for restricted stock	$	8,690			$	10,467		$	10,934
	Unrecognized stock compensation expense for restricted stock awards and options	22,532				14,482			19,530
	Tax benefit recognized for stock compensation expense	3,424				4,034			4,259
	Weighted average amortization (years)	2.6				1.6			2.1
Restricted stock and stock options outstanding under the Company Financial Incentive Stock Program	The following table reflects TCF's restricted stock and stock option transactions under the Program since December 31, 2011.
		Restricted Stock												Stock Options
		Shares			Price Range							Weighted-		Shares		Price Range					Weighted-	Weighted-
												Average									Average	Average
												Grant Date									Remaining	Exercise
												Fair Value									Contractual	Price
																					Life in Years
	Outstanding at December 31, 2011	2,284,114			$	6.16		-		$	28.64	$	12.95	2,198,744		$	12.85	-	$	15.75	5.72	$	14.43
	Granted	1,769,700			7.73			-		11.56		9.27		—		—		-	—		—	—
	Forfeited/canceled	(322,908	)		7.73			-		28.02		10.13		(121,640	)	15.75		-	15.75		—	15.75
	Vested	(518,671	)		7.57			-		28.64		13.42		—		—		-	—		—	—
	Outstanding at December 31, 2012	3,212,235			6.16			-		25.18		11.13		2,077,104		12.85		-	15.75		4.22	14.35
	Granted	493,650			12.47			-		15.17		13.55		—		—		-	—		—	—
	Forfeited/canceled	(120,313	)		9.65			-		17.37		12.75		(451,104	)	15.75		-	15.75		—	15.75
	Vested	(230,277	)		9.48			-		25.18		16.04		—		—		-	—		—	—
	Outstanding at December 31, 2013	3,355,295			6.16			-		15.17		11.09		1,626,000		12.85		-	15.75		4.36	13.97
	Granted	1,120,750			13.84			-		16.02		15.61		—		—		-	—		—	—
	Exercised	—			—			-		—		—		(47,000	)	15.75		-	15.75		—	15.75
	Forfeited/canceled	(108,490	)		6.8			-		15.79		13.06		—		—		-	—		—	—
	Vested	(1,509,061	)		8.35			-		14.9		11.21		—		—		-	—		—	—
	Outstanding at December 31, 2014	2,858,494			6.16			-		16.02		12.73		1,579,000		12.85		-	15.75		2.98	13.91
	Exercisable at December 31, 2014	N.A.										N.A.		1,579,000		12.85		-	15.75			13.91
	N.A. Not Applicable
Schedule of additional valuation and related assumption information for stock option plans	Valuation and related assumption information for TCF's stock option plans related to options issued in 2008 is presented below and no stock options were subsequently issued through December 31, 2014.
	Expected volatility				28.50%
	Weighted-average volatility				28.50%
	Expected dividend yield				3.50%
	Expected term (years)	6.25		-	6.75
	Risk-free interest rate	2.58	%	-	2.91%

Employee_Benefit_Plans_Tables

Employee Benefit Plans (Tables)	12 Months Ended
	Dec. 31, 2014
Compensation and Retirement Disclosure [Abstract]
Schedule of status of the Pension Plan and the Postretirement Plan	The following table sets forth the status of the Pension Plan and the Postretirement Plan.
		Pension Plan								Postretirement Plan
		Year Ended December 31,
	(In thousands)	2014				2013				2014			2013
	Change in benefit obligation:
	Benefit obligation, beginning of period	$	41,870			$	45,037			$	5,217		$	6,675
	Interest cost on projected benefit obligation	1,587				1,292				198			174
	Actuarial (gain) loss	1,862				(2,196		)		(63		)	(1,241		)
	Benefits paid	(5,829		)		(2,263		)		(368		)	(391		)
	Projected benefit obligation, end of period	39,490				41,870				4,984			5,217
	Change in fair value of plan assets:
	Fair value of plan assets, beginning of period	51,018				53,617				—			—
	Actual gain (loss) on plan assets	(511		)		(336		)		—			—
	Benefits paid	(5,829		)		(2,263		)		(368		)	(391		)
	TCF contributions	—				—				368			391
	Fair value of plan assets, end of period	44,678				51,018				—			—
	Funded status of plans, end of period	$	5,188			$	9,148			$	(4,984	)	$	(5,217	)
	Amounts recognized in the Consolidated Statements of Financial Condition:
	Prepaid (accrued) benefit cost, end of period	$	5,188			$	9,148			$	(4,984	)	$	(5,217	)
	Prior service cost included in accumulated other comprehensive loss	—				—				(331		)	(378		)
	Accumulated other comprehensive loss, before tax	—				—				(331		)	(378		)
	Total recognized asset (liability)	$	5,188			$	9,148			$	(5,315	)	$	(5,595	)
Schedule of balances of Pension Plan investments	The following table presents the balances of TCF's Pension Plan investments at fair value on a recurring basis.
		Pension Plan
		Year Ended December 31,
	(In thousands)	2014					2013
	Level 1:
	U.S. Treasury bills	$	—				$	47,999
	Fixed income mutual funds	22,532					—
	Money market mutual funds	16,088					3,019
	Cash	71					—
	Level 2:
	Collective investment fund	4,961			—		—
	Mortgage-backed securities	1,026					—
	Total Pension Plan assets held in trust	$	44,678				$	51,018
Schedule of changes recognized in accumulated other comprehensive (income) loss	The following table sets forth the changes recognized in accumulated other comprehensive loss that are attributed to the Postretirement Plan.
		Postretirement Plan
		Year Ended December 31,
	(In thousands)	2014				2013				2012
	Accumulated other comprehensive loss at the beginning of the year	$	(378	)		$	(424	)		$	(301	)
	Prior service cost	—				—				(151		)
	Amortization (recognized in net periodic benefit cost):
	Prior service credit	47				46				28
	Total recognized in other comprehensive income (loss)	47				46				(123		)
	Accumulated other comprehensive loss at end of year, before tax	$	(331	)		$	(378	)		$	(424	)
Schedule of net periodic benefit cost included in compensation and employee benefits expense for cash balance Pension Plan and Postretirement Plan	The following tables set forth the net periodic benefit plan (income) cost included in compensation and employee benefits expense for the Pension Plan and the Postretirement Plan.
		Pension Plan
		Year Ended December 31,
	(In thousands)	2014				2013				2012
	Interest cost	$	1,587			$	1,292			$	1,763
	Loss on plan assets	511				336				277
	Recognized actuarial (gain) loss	1,862				(2,196		)		289
	Net periodic benefit plan (income) cost	$	3,960			$	(568	)		$	2,329
		Postretirement Plan
		Year Ended December 31,
	(In thousands)	2014				2013				2012
	Interest cost	$	198			$	174			$	293
	Recognized actuarial (gain) loss	(63		)		(1,241		)		(721		)
	Amortization of prior service cost	(47		)		(46		)		(28		)
	Net periodic benefit plan (income) cost	$	88			$	(1,113	)		$	(456	)
Schedule of discount rate and expected long-term rate of return on plan assets used to determine the estimated net benefit plan cost	The discount rate and expected long-term rate of return on plan assets used to determine the estimated net benefit plan cost were as follows.
		Pension Plan									Postretirement Plan
		Year Ended December 31,									Year Ended December 31,
	Assumptions used to determine estimated net benefit plan cost	2014			2013			2012			2014		2013			2012
	Discount rate	4	%		3	%		4	%		4	%	2.75	%		4	%
	Expected long-term rate of return on plan assets	1.5			1.5			1.5			N.A.		N.A.			N.A.
	N.A. Not Applicable.
Schedule of expected future benefit payments used to determine projected benefit obligations	The following are expected future benefit payments used to determine projected benefit obligations.
	(In thousands)	Pension Plan				Postretirement Plan
	2015	$	4,209			$	505
	2016	3,549				486
	2017	2,881				466
	2018	3,036				445
	2019	3,138				424
	2020 - 2024	12,284				1,801
Schedule of assumed health care cost trend rates for the Postretirement Plan	The following table presents assumed health care cost trend rates for the Postretirement Plan at December 31, 2014 and 2013.
		2014			2013
	Health care cost trend rate assumed for next year	5.8	%		6	%
	Final health care cost trend rate	5	%		5	%
	Year that final health care trend rate is reached	2023			2023
Schedule of 1% change in assumed health care cost trend rates	Assumed health care cost trend rates have an effect on the amounts reported for the Postretirement Plan. A 1.0% change in assumed health care cost trend rates would have the following effect.
		1-Percentage-Point
	(In thousands)	Increase				Decrease
	Effect on total service and interest cost components	$	9			$	(9	)
	Effect on postretirement benefits obligations	217				(196		)

Financial_Instruments_with_Off1

Financial Instruments with Off-Balance Sheet Risk (Tables)	12 Months Ended
	Dec. 31, 2014
Financial Instruments with Off-Balance Sheet Risk
Summary of financial instruments with off-balance sheet risk	Financial instruments with off-balance sheet risk are summarized as follows.
		At December 31,
	(In thousands)	2014		2013
	Commitments to extend credit:
	Consumer real estate and other	$	1,314,826	$	1,274,006
	Commercial	609,618		482,777
	Leasing and equipment finance	140,261		158,321
	Total commitments to extend credit	2,064,705		1,915,104
	Standby letters of credit and guarantees on industrial revenue bonds	14,676		13,364
	Total	$	2,079,381	$	1,928,468

Derivative_Instruments_Tables

Derivative Instruments (Tables)	12 Months Ended
	Dec. 31, 2014
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Summary of derivative instruments	The following tables summarize TCF's outstanding derivative instruments as of December 31, 2014 and 2013. See Note 19, Fair Value Disclosures for additional information.
		At December 31, 2014
	(In thousands)	Notional			Gross Amounts		Gross Amounts			Net Amount
		Amount			Recognized		Offset			Presented(1)
	Derivative Assets:
	Net investment hedges	$	42,165		$	509	$	—		$	509
	Forward foreign exchange contracts not designated as hedges	275,962			2,702		(1,179		)	1,523
	Swap agreements	101,166			1,798		—			1,798
	Interest rate lock commitments	15,124			285		—			285
	Total derivative assets				$	5,294	$	(1,179	)	$	4,115
	Derivative Liabilities:
	Forward foreign exchange contracts not designated as hedges	$	189,310		$	177	$	(29	)	$	148
	Swap agreements	114,970			2,498		(2,498		)	—
	Total derivative liabilities				$	2,675	$	(2,527	)	$	148
		At December 31, 2013
	(In thousands)	Notional			Gross Amounts		Gross Amounts			Net Amount
		Amount			Recognized		Offset			Presented(1)
	Derivative Assets:
	Forward foreign exchange contracts not designated as hedges	$	98,847		$	151	$	(151	)	$	—
	Swap agreements	13,500			131		—			131
	Total derivative assets				$	282	$	(151	)	$	131
	Derivative Liabilities:
	Net investment hedges	$	32,761		$	87	$	—		$	87
	Forward foreign exchange contracts not designated as hedges	363,475			834		—			834
	Swap agreements	41,358			1,031		(1,031		)	—
	Total derivative liabilities				$	1,952	$	(1,031	)	$	921
	-1	All amounts were offset in the Consolidated Statements of Financial Condition.
Schedule of pre-tax impact of derivative activity	The following table summarizes the pre-tax impact of derivative activity within the Consolidated Statements of Income and the Consolidated Statements of Comprehensive Income, by accounting designation.
		Year Ended December 31,
	(In thousands)	2014			2013		2012
	Consolidated Statements of Income:
	Non-interest income:
	Swap agreements	$	(79	)	$	—	$	—
	Interest rate lock commitments	285			—		—
	Non-interest expense:
	Cash flow hedge	—			—		(6		)
	Forward foreign exchange contracts not designated as hedges	38,752			25,170		(7,524		)
	Net realized gain (loss)	$	38,958		$	25,170	$	(7,530	)
	Consolidated Statements of Comprehensive Income:
	Other comprehensive income (loss):
	Net investment hedges	$	3,126		$	1,625	$	(630	)
	Net unrealized gain (loss)	$	3,126		$	1,625	$	(630	)

Fair_Values_Disclosures_Tables

Fair Values Disclosures (Tables)	12 Months Ended
	Dec. 31, 2014
Fair Value Disclosures [Abstract]
Balances of assets and liabilities measured at fair value on a recurring and non-recurring basis	The following tables present the balances of assets and liabilities measured at fair value on a recurring and non-recurring basis.
		Fair Value Measurements at December 31, 2014
	(In thousands)	Level 1			Level 2			Level 3			Total
	Recurring Fair Value Measurements:
	Securities available for sale:
	Mortgage-backed securities:
	U.S. Government sponsored enterprises and federal agencies	$	—		$	463,239		$	—		$	463,239
	Other	—			—			55			55
	Loans and leases held for sale	—			—			3,308			3,308
	Forward foreign exchange contracts(1)	—			3,211			—			3,211
	Swap agreements(1)	—			1,798			—			1,798
	Interest rate lock commitments(1)	—			—			285			285
	Forward loan sales commitments	—			—			19			19
	Assets held in trust for deferred compensation plans	18,703			—			—			18,703
	Total assets	$	18,703		$	468,248		$	3,667		$	490,618
	Forward foreign exchange contracts(1)	$	—		$	177		$	—		$	177
	Swap agreements(1)	—			1,877			621			2,498
	Forward loan sales commitments	—			—			42			42
	Liabilities held in trust for deferred compensation plans	18,703			—			—			18,703
	Total liabilities	$	18,703		$	2,054		$	663		$	21,420
	Non-recurring Fair Value Measurements:
	Securities held to maturity	$	—		$	—		$	1,516		$	1,516
	Loans	—			—			164,897			164,897
	Interest-only strips	—			—			41,204			41,204
	Other real estate owned:
	Consumer	—			—			40,502			40,502
	Commercial	—			4,839			8,866			13,705
	Repossessed and returned assets	—			1,563			1,425			2,988
	Total non-recurring fair value measurements	$	—		$	6,402		$	258,410		$	264,812
		Fair Value Measurements at December 31, 2013
	(In thousands)	Level 1			Level 2			Level 3			Total
	Recurring Fair Value Measurements:
	Securities available for sale:
	Mortgage-backed securities:
	U.S. Government sponsored enterprises and federal agencies	$	—		$	548,037		$	—		$	548,037
	Other	—			—			93			93
	Other securities	2,934			—			—			2,934
	Forward foreign exchange contracts(1)	—			151			—			151
	Swap agreements(1)	—			131			—			131
	Assets held in trust for deferred compensation plans	16,724			—			—			16,724
	Total assets	$	19,658		$	548,319		$	93		$	568,070
	Forward foreign exchange contracts(1)	$	—		$	921		$	—		$	921
	Swap agreements(1)	—			132			899			1,031
	Liabilities held in trust for deferred compensation plans	16,724			—			—			16,724
	Total liabilities	$	16,724		$	1,053		$	899		$	18,676
	Non-recurring Fair Value Measurements:
	Securities held to maturity	$	—		$	—		$	1,902		$	1,902
	Loans	—			—			214,183			214,183
	Interest-only strips	—			—			33,098			33,098
	Other real estate owned:
	Consumer	—			—			40,355			40,355
	Commercial	—			—			14,088			14,088
	Repossessed and returned assets	—			1,537			730			2,267
	Total non-recurring fair value measurements	$	—		$	1,537		$	304,356		$	305,893
	-1	As permitted under GAAP, TCF has elected to net derivative receivables and derivative payables with the related cash collateral received and paid when a legally enforceable master netting agreement exists. For purposes of this table, the derivative receivable and derivative payable balances are presented gross of this netting adjustment.
Schedule of reconciliation of the assets measured at fair value on a recurring basis	The following table presents changes in Level 3 assets and liabilities measured at fair value on a recurring basis.
	(In thousands)	Securities Available			Loans and Leases Held for Sale			Interest			Forward Loan Sales Commitments			Swap Agreements
		for Sale						Rate Lock
								Commitments
	Asset (liability) balance, December 31, 2011	$	1,450		$	—		$	—		$	—		$	—
	Transfers out of Level 3	(1,098		)	—			—			—			—
	Total net losses included in:
	Net loss	—			—			—			—			(150		)
	Other comprehensive loss	(100		)	—			—			—			—
	Purchases	—			—			—			—			(1,434		)
	Principal paydowns / settlements	(125		)	—			—			—			357
	Asset (liability) balance, December 31, 2012	127			—			—			—			(1,227		)
	Principal paydowns / settlements	(34		)	—			—			—			328
	Asset (liability) balance, December 31, 2013	93			—			—			—			(899		)
	Total net gains (losses) included in:
	Net income	—			72			285			(23		)	(47		)
	Sales	—			(39,246		)	—			—			—
	Purchases / originations	—			42,482			—			—			—
	Principal paydowns / settlements	(38		)	—			—			—			325
	Asset (liability) balance, December 31, 2014	$	55		$	3,308		$	285		$	(23	)	$	(621	)
Schedule of reconciliation of the net derivative assets and liabilities measured at fair value on a recurring basis	The following table presents changes in Level 3 assets and liabilities measured at fair value on a recurring basis.
	(In thousands)	Securities Available			Loans and Leases Held for Sale			Interest			Forward Loan Sales Commitments			Swap Agreements
		for Sale						Rate Lock
								Commitments
	Asset (liability) balance, December 31, 2011	$	1,450		$	—		$	—		$	—		$	—
	Transfers out of Level 3	(1,098		)	—			—			—			—
	Total net losses included in:
	Net loss	—			—			—			—			(150		)
	Other comprehensive loss	(100		)	—			—			—			—
	Purchases	—			—			—			—			(1,434		)
	Principal paydowns / settlements	(125		)	—			—			—			357
	Asset (liability) balance, December 31, 2012	127			—			—			—			(1,227		)
	Principal paydowns / settlements	(34		)	—			—			—			328
	Asset (liability) balance, December 31, 2013	93			—			—			—			(899		)
	Total net gains (losses) included in:
	Net income	—			72			285			(23		)	(47		)
	Sales	—			(39,246		)	—			—			—
	Purchases / originations	—			42,482			—			—			—
	Principal paydowns / settlements	(38		)	—			—			—			325
	Asset (liability) balance, December 31, 2014	$	55		$	3,308		$	285		$	(23	)	$	(621	)
Fair Value, Option, Quantitative Disclosures	The following table presents the difference between the aggregate fair value and aggregate unpaid principal balance of these loans held for sale as of December 31, 2014. There were no loans held for sale reported under the fair value option as of December 31, 2013.
	(In thousands)	At December 31, 2014
	Fair value carrying amount	$	3,308
	Aggregate unpaid principal amount	3,205
	Fair value carrying amount less aggregate unpaid principal	$	103
Fair Value of Assets and Liabilities, Including Hierarchy Level
					Estimated Fair Value at December 31, 2014
	(In thousands)	Carrying Amount			Level 1			Level 2			Level 3			Total
	Financial instrument assets:
	Investments	$	85,492		$	—		$	85,492		$	—		$	85,492
	Securities held to maturity	214,454			—			217,418			4,916			222,334
	Loans and leases held for sale	132,266			—			—			139,370			139,370
	Loans:
	Consumer real estate	5,682,364			—			—			5,836,770			5,836,770
	Commercial real estate	2,624,255			—			—			2,575,625			2,575,625
	Commercial business	533,410			—			—			512,083			512,083
	Equipment finance	1,806,808			—			—			1,787,271			1,787,271
	Inventory finance	1,877,090			—			—			1,864,786			1,864,786
	Auto finance	1,915,061			—			—			1,927,384			1,927,384
	Other	24,144			—			—			18,724			18,724
	Allowance for loan losses(1)	(164,169		)	—			—			—			—
	Interest-only strips(2)	69,789			—			—			73,058			73,058
	Total financial instrument assets	$	14,800,964		$	—		$	302,910		$	14,739,987		$	15,042,897
	Financial instrument liabilities:
	Deposits	$	15,449,882		$	12,400,693		$	3,063,850		$	—		$	15,464,543
	Long-term borrowings	1,232,065			—			1,246,221			8,054			1,254,275
	Total financial instrument liabilities	$	16,681,947		$	12,400,693		$	4,310,071		$	8,054		$	16,718,818
	Financial instruments with off-balance sheet risk:(3)
	Commitments to extend credit	$	25,885		$	—		$	25,885		$	—		$	25,885
	Standby letters of credit	(47		)	—			(47		)	—			(47		)
	Total financial instruments with off-balance sheet risk	$	25,838		$	—		$	25,838		$	—		$	25,838
	-1	Expected credit losses are included in the estimated fair values.
	-2	Carrying amounts are included in other assets.
	-3	Positive amounts represent assets, negative amounts represent liabilities.
					Estimated Fair Value at December 31, 2013
	(In thousands)	Carrying Amount			Level 1			Level 2			Level 3			Total
	Financial instrument assets:
	Investments	$	94,326		$	—		$	94,326		$	—		$	94,326
	Securities held to maturity	19,912			—			14,610			5,302			19,912
	Loans and leases held for sale	79,768			—			—			84,341			84,341
	Loans:
	Consumer real estate	6,339,326			—			—			6,279,328			6,279,328
	Commercial real estate	2,743,697			—			—			2,673,825			2,673,825
	Commercial business	404,655			—			—			392,947			392,947
	Equipment finance	1,546,134			—			—			1,534,905			1,534,905
	Inventory finance	1,664,377			—			—			1,653,345			1,653,345
	Auto finance	1,239,386			—			—			1,256,357			1,256,357
	Other	26,743			—			—			25,216			25,216
	Allowance for loan losses(1)	(252,230		)	—			—			—			—
	Interest-only strips(2)	84,561			—			—			85,265			85,265
	Total financial instrument assets	$	13,990,655		$	—		$	108,936		$	13,990,831		$	14,099,767
	Financial instrument liabilities:
	Deposits	$	14,432,776		$	12,006,364		$	2,434,946		$	—		$	14,441,310
	Long-term borrowings	1,483,325			—			1,496,017			10,838			1,506,855
	Total financial instrument liabilities	$	15,916,101		$	12,006,364		$	3,930,963		$	10,838		$	15,948,165
	Financial instruments with off-balance sheet risk:(3)
	Commitments to extend credit	$	29,057		$	—		$	29,057		$	—		$	29,057
	Standby letters of credit	(52		)	—			(52		)	—			(52		)
	Total financial instruments with off-balance sheet risk	$	29,005		$	—		$	29,005		$	—		$	29,005
	-1	Expected credit losses are included in the estimated fair values.
	-2	Carrying amounts are included in other assets.
	-3	Positive amounts represent assets, negative amounts represent liabilities.

Earnings_Per_Common_Share_Tabl

Earnings Per Common Share (Tables)	12 Months Ended
	Dec. 31, 2014
Earnings Per Share [Abstract]
Computation of basic and diluted earnings per common share
		At or For the Year Ended December 31,
	(Dollars in thousands, except per-share data)	2014			2013			2012
	Basic Earnings (Loss) Per Common Share:
	Net income (loss) attributable to TCF Financial Corporation	$	174,187		$	151,668		$	(212,884	)
	Preferred stock dividends	(19,388		)	(19,065		)	(5,606		)
	Net income (loss) available to common stockholders	154,799			132,603			(218,490		)
	Earnings allocated to participating securities	40			71			50
	Earnings (loss) allocated to common stock	$	154,759		$	132,532		$	(218,540	)
	Weighted-average shares outstanding	166,542,848			164,229,421			162,288,902
	Restricted stock	(2,961,413		)	(3,213,417		)	(3,020,094		)
	Weighted-average common shares outstanding for basic earnings (loss) per common share	163,581,435			161,016,004			159,268,808
	Basic earnings (loss) per common share	$	0.95		$	0.82		$	(1.37	)
	Diluted Earnings (Loss) Per Common Share:
	Earnings (loss) allocated to common stock	$	154,759		$	132,532		$	(218,540	)
	Weighted-average common shares outstanding used in basic earnings (loss) per common share calculation	163,581,435			161,016,004			159,268,808
	Net dilutive effect of:
	Non-participating restricted stock	250,499			719,459			—
	Stock options	252,892			191,092			—
	Weighted-average common shares outstanding for diluted earnings (loss) per common share	164,084,826			161,926,555			159,268,808
	Diluted earnings (loss) per common share	$	0.94		$	0.82		$	(1.37	)

Other_Expense_Tables

Other Expense (Tables)	12 Months Ended
	Dec. 31, 2014
Other Income and Expenses [Abstract]
Other Expense	Other expense consisted of the following.
		Year Ended December 31,
	(In thousands)	2014		2013		2012
	Loan and lease processing	$	20,294	$	13,787	$	9,567
	Professional fees	18,949		18,642		13,608
	Card processing and issuance cost	16,588		15,868		15,586
	Outside processing	13,288		13,767		12,919
	Telecommunications	11,911		11,720		11,735
	Travel	11,481		12,810		11,740
	Other	87,393		81,183		88,742
	Total other expense	$	179,904	$	167,777	$	163,897

Business_Segments_Tables

Business Segments (Tables)	12 Months Ended
	Dec. 31, 2014
Segment Reporting [Abstract]
Reportable segments, including a reconciliation of consolidated totals	The following tables set forth certain information for each of TCF's reportable segments, including a reconciliation of TCF's consolidated totals.
	(In thousands)	Lending		Funding			Support Services			Eliminations and Other(1)			Consolidated
	At or For the Year Ended December 31, 2014:
	Net interest income	$	592,409	$	226,327		$	166		$	(3,273	)	$	815,629
	Provision for credit losses	92,800		2,937			—			—			95,737
	Non-interest income	211,166		220,568			140,779			(139,246		)	433,267
	Non-interest expense	426,290		434,141			147,549			(136,203		)	871,777
	Income tax expense (benefit)	102,398		3,722			(1,932		)	(4,422		)	99,766
	Income (loss) after income tax expense (benefit)	182,087		6,095			(4,672		)	(1,894		)	181,616
	Income attributable to non-controlling interest	7,429		—			—			—			7,429
	Preferred stock dividends	—		—			19,388			—			19,388
	Net income (loss) available to common stockholders	$	174,658	$	6,095		$	(24,060	)	$	(1,894	)	$	154,799
	Total assets	$	16,871,154	$	6,488,853		$	239,425		$	(4,204,821	)	$	19,394,611
	Revenues from external customers:
	Interest income	$	852,019	$	22,210		$	—		$	—		$	874,229
	Non-interest income	211,166		220,506			1,595			—			433,267
	Total	$	1,063,185	$	242,716		$	1,595		$	—		$	1,307,496
	At or For the Year Ended December 31, 2013:
	Net interest income	$	568,286	$	237,289		$	3		$	(2,954	)	$	802,624
	Provision for credit losses	115,408		2,960			—			—			118,368
	Non-interest income	168,387		235,238			136,584			(136,151		)	404,058
	Non-interest expense	401,326		442,557			139,864			(138,478		)	845,269
	Income tax expense (benefit)	76,663		9,750			8			(2,076		)	84,345
	Income (loss) after income tax expense (benefit)	143,276		17,260			(3,285		)	1,449			158,700
	Income attributable to non-controlling interest	7,032		—			—			—			7,032
	Preferred stock dividends	—		—			19,065			—			19,065
	Net income (loss) available to common stockholders	$	136,244	$	17,260		$	(22,350	)	$	1,449		$	132,603
	Total assets	$	16,197,449	$	7,862,779		$	228,863		$	(5,909,251	)	$	18,379,840
	Revenues from external customers:
	Interest income	$	840,250	$	24,290		$	—		$	—		$	864,540
	Non-interest income	168,387		235,185			486			—			404,058
	Total	$	1,008,637	$	259,475		$	486		$	—		$	1,268,598
	At or For the Year Ended December 31, 2012:
	Net interest income	$	524,358	$	258,283		$	41		$	(2,663	)	$	780,019
	Provision for credit losses	245,355		2,088			—			—			247,443
	Non-interest income	138,514		338,895			140,784			(127,770		)	490,423
	Non-interest expense	367,172		969,805			152,677			(127,100		)	1,362,554
	Income tax expense (benefit)	13,272		(135,432		)	(7,790		)	(2,908		)	(132,858		)
	Income (loss) after income tax expense (benefit)	37,073		(239,283		)	(4,062		)	(425		)	(206,697		)
	Income attributable to non-controlling interest	6,187		—			—			—			6,187
	Preferred stock dividends	—		—			5,606			—			5,606
	Net income (loss) available to common stockholders	$	30,886	$	(239,283	)	$	(9,668	)	$	(425	)	$	(218,490	)
	Total assets	$	15,694,693	$	7,249,958		$	148,513		$	(4,867,247	)	$	18,225,917
	Revenues from external customers:
	Interest income	$	842,718	$	41,905		$	—		$	—		$	884,623
	Non-interest income	138,514		338,848			13,061			—			490,423
	Total	$	981,232	$	380,753		$	13,061		$	—		$	1,375,046
	-1	Other includes the unallocated portion of pension and other postretirement benefits (expenses) attributable to the annual determination of actuarial gains and losses.

Parent_Company_Financial_Infor1

Parent Company Financial Information (Tables)	12 Months Ended
	Dec. 31, 2014
Condensed Financial Information of Parent Company Only Disclosure [Abstract]
Schedule of condensed statements of financial position	Condensed Statements of Financial Condition
		At December 31,
	(In thousands)	2014			2013
	Assets:
	Cash and cash equivalents	$	71,781		$	62,775
	Investment in bank subsidiary	2,037,781			1,863,563
	Accounts receivable from bank subsidiary	13,862			21,706
	Other assets	12,628			19,498
	Total assets	$	2,136,052		$	1,967,542
	Liabilities and Equity:
	Other liabilities	$	14,403		$	14,574
	Total liabilities	14,403			14,574
	Equity	2,121,649			1,952,968
	Total liabilities and equity	$	2,136,052		$	1,967,542
Schedule of Condensed Statements of Income	Condensed Statements of Income
		Year Ended December 31,
	(In thousands)	2014			2013			2012
	Interest income	$	365		$	419		$	355
	Interest expense	—			—			7,952
	Net interest income (expense)	365			419			(7,597		)
	Non-interest income:
	Dividends from TCF Bank	19,000			—			18,000
	Affiliate service fees	22,461			23,338			17,089
	Other	1,178			407			12,936
	Total non-interest income	42,639			23,745			48,025
	Non-interest expense:
	Compensation and employee benefits	21,193			22,108			14,703
	Occupancy and equipment	338			322			298
	Other	3,436			3,352			15,731
	Total non-interest expense	24,967			25,782			30,732
	Income (loss) before income tax benefit and equity in undistributed earnings of subsidiaries	18,037			(1,618		)	9,696
	Income tax benefit	52			309			2,766
	Income (loss) before equity in undistributed earnings of subsidiaries	18,089			(1,309		)	12,462
	Equity (deficit) in undistributed earnings of bank subsidiary	156,098			152,977			(225,346		)
	Net income (loss)	174,187			151,668			(212,884		)
	Preferred stock dividends	19,388			19,065			5,606
	Net income (loss) available to common stockholders	$	154,799		$	132,603		$	(218,490	)
Schedule of condensed statements of cash flows	Condensed Statements of Cash Flows
		Year Ended December 31,
	(In thousands)	2014			2013			2012
	Cash flows from operating activities:
	Net income (loss)	$	174,187		$	151,668		$	(212,884	)
	Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
	(Equity) deficit in undistributed earnings of bank subsidiary	(156,098		)	(152,977		)	225,346
	(Gains) on sales of assets, net	(1,177		)	(350		)	(13,116		)
	Other, net	16,430			9,962			9,561
	Net cash provided by (used in) operating activities	33,342			8,303			8,907
	Cash flows from investing activities:
	Capital contributions to bank subsidiary	—			—			(192,000		)
	Proceeds from sales of securities available for sale	2,813			—			—
	Proceeds from sales of other securities	—			—			14,550
	Purchases of premises and equipment	(260		)	(148		)	(6		)
	Proceeds from sales of premises and equipment	91			—			—
	Other, net	—			869			—
	Net cash provided by (used in) investing activities	2,644			721			(177,456		)
	Cash flows from financing activities:
	Net proceeds from public offerings of preferred stock	—			—			263,240
	Dividends paid on preferred stock	(19,388		)	(19,065		)	(5,606		)
	Dividends paid on common stock	(32,731		)	(32,227		)	(31,904		)
	Redemption of trust preferred securities	—			—			(115,010		)
	Interest paid on trust preferred securities	—			—			(8,757		)
	Shares sold to TCF employee benefit plans	23,083			20,179			19,462
	Stock compensation tax (expense) benefit	1,316			(473		)	(659		)
	Exercise of stock options	740			—			—
	Net cash provided by (used in) financing activities	(26,980		)	(31,586		)	120,766
	Net change in cash and due from banks	9,006			(22,562		)	(47,783		)
	Cash and due from banks at beginning of period	62,775			85,337			133,120
	Cash and due from banks at end of period	$	71,781		$	62,775		$	85,337

Accumulated_Other_Comprehensiv1

Accumulated Other Comprehensive Income (Loss) (Tables)	12 Months Ended
	Dec. 31, 2014
Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
Summary of components of other comprehensive income and the related tax effects	The components of other comprehensive income (loss) and the related tax effects are presented in the tables below.
	(In thousands)	Before Tax			Tax Effect			Net of Tax
	Year Ended December 31, 2014:
	Securities available for sale:
	Unrealized gains (losses) arising during the period	$	29,071		$	(10,932	)	$	18,139
	Reclassification of net (gains) losses to net income	(76		)	29			(47		)
	Net unrealized gains (losses)	28,995			(10,903		)	18,092
	Net investment hedges:
	Unrealized gains (losses) arising during the period	3,126			(1,181		)	1,945
	Foreign currency translation adjustment:(1)
	Unrealized gains (losses) arising during the period	(3,704		)	—			(3,704		)
	Recognized postretirement prior service cost:
	Reclassification of net (gains) losses to net income	(47		)	17			(30		)
	Total other comprehensive income (loss)	$	28,370		$	(12,067	)	$	16,303
	Year Ended December 31, 2013:
	Securities available for sale:
	Unrealized gains (losses) arising during the period	$	(61,177	)	$	23,053		$	(38,124	)
	Reclassification of net (gains) losses to net income	(860		)	324			(536		)
	Net unrealized gains (losses)	(62,037		)	23,377			(38,660		)
	Net investment hedges:
	Unrealized gains (losses) arising during the period	1,625			(614		)	1,011
	Foreign currency translation adjustment:(1)
	Unrealized gains (losses) arising during the period	(1,979		)	—			(1,979		)
	Recognized postretirement prior service cost:
	Reclassification of net (gains) losses to net income	(46		)	18			(28		)
	Total other comprehensive income (loss)	$	(62,437	)	$	22,781		$	(39,656	)
	Year Ended December 31, 2012:
	Securities available for sale:
	Unrealized gains (losses) arising during the period	$	19,794		$	(7,252	)	$	12,542
	Reclassification of net (gains) losses to net income	(89,879		)	32,745			(57,134		)
	Net unrealized gains (losses)	(70,085		)	25,493			(44,592		)
	Net investment hedges:
	Unrealized gains (losses) arising during the period	(630		)	239			(391		)
	Foreign currency translation adjustment:(1)
	Unrealized gains (losses) arising during the period	531			—			531
	Recognized postretirement prior service cost:
	Unrealized gains (losses) arising during the period	151			(66		)	85
	Reclassification of net (gains) losses to net income	(28		)	12			(16		)
	Total other comprehensive income (loss)	$	(70,061	)	$	25,678		$	(44,383	)
	-1	Foreign investments are deemed to be permanent in nature and therefore TCF does not provide for taxes on foreign currency translation adjustments.
Schedule of accumulated other comprehensive income	Accumulated other comprehensive income (loss) balances are presented in the tables below.
	(In thousands)	Securities			Net			Foreign			Recognized			Total
		Available			Investment			Currency			Postretirement Prior
		for Sale			Hedges			Translation			Service Cost
								Adjustment
	At or For the Year Ended December 31, 2014:
	Balance, beginning of period	$	(26,983	)	$	591		$	(1,056	)	$	235		$	(27,213	)
	Other comprehensive income (loss)	18,139			1,945			(3,704		)	—			16,380
	Amounts reclassified from accumulated other comprehensive income (loss)	(47		)	—			—			(30		)	(77		)
	Net other comprehensive income (loss)	18,092			1,945			(3,704		)	(30		)	16,303
	Balance, end of period	$	(8,891	)	$	2,536		$	(4,760	)	$	205		$	(10,910	)
	At or For the Year Ended December 31, 2013:
	Balance, beginning of period	$	11,677		$	(420	)	$	923		$	263		$	12,443
	Other comprehensive income (loss)	(38,124		)	1,011			(1,979		)	—			(39,092		)
	Amounts reclassified from accumulated other comprehensive income (loss)	(536		)	—			—			(28		)	(564		)
	Net other comprehensive income (loss)	(38,660		)	1,011			(1,979		)	(28		)	(39,656		)
	Balance, end of period	$	(26,983	)	$	591		$	(1,056	)	$	235		$	(27,213	)
	At or For the Year Ended December 31, 2012:
	Balance, beginning of period	$	56,269		$	(29	)	$	392		$	194		$	56,826
	Other comprehensive income (loss)	12,542			(391		)	531			85			12,767
	Amounts reclassified from accumulated other comprehensive income (loss)	(57,134		)	—			—			(16		)	(57,150		)
	Net other comprehensive income (loss)	(44,592		)	(391		)	531			69			(44,383		)
	Balance, end of period	$	11,677		$	(420	)	$	923		$	263		$	12,443

Summary_of_Significant_Account2

Summary of Significant Accounting Policies (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Non-accrual Loans and Leases
Maturity period to be considered to place consumer loans, other than real estate and auto loans, on non-accrual status	120 days
Minimum period to be considered for related third-party first mortgage liens to be past due before Junior lien loans are placed on non-accrual status	90 days
Other Real Estate Owned
Other real estate owned	$65,700,000	$68,900,000
Repossessed and returned equipment	$3,500,000	$3,500,000
Minimum
Non-accrual Loans and Leases
Maturity period to be considered to place commercial loans on non-accrual status	90 days
Sustained repayment performance period to be considered until when loans and leases are to be reported as non-accrual loans	6 months
Sustained repayment performance period to be considered until when income on loans and leases are to be recognized on a cash basis	6 months
Maximum
Allowance for Loan and Lease Losses
Maturity period to be considered to charge off consumer real estate loans	150 days
Maturity period to be considered to charge off auto finance loans in full	120 days
Maturity period to be considered for deposit account overdrafts to be charged off	60 days
Non-accrual Loans and Leases
Number of days delinquent to be considered until when income on loans and leases are to be recognized on a cash basis	60 days
Deposit Account Overdrafts
Number of days from the date of overdraft considered to report net losses on uncollectible overdrafts as net charge-offs in the allowance for loan and lease losses	60 days

Cash_and_Due_from_Banks_Detail

Cash and Due from Banks (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Cash and Cash Equivalents [Abstract]
Reserve in cash on hand or at the Federal Reserve as required by Federal Reserve regulations	$98.70	$95.50
Total restricted cash balance	67.8	46.1
Cash held in interest-bearing accounts	$842.10	$613.30

Investments_Details

Investments (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
	bank
Investments
Federal Home Loan Bank stock, at cost	$47,914	$56,845
Federal Reserve Bank stock, at cost	37,578	37,481
Total investments	$85,492	$94,326
Number of Federal Home Loan Banks liable for repayment	12
Federal Reserve Bank stock required to be held by the entity as a percentage of its capital surplus	6.00%
Yield on investments, no stated maturity (as a percent)	4.25%	3.93%

Securities_Available_for_Sale_2

Securities Available for Sale and Securities Held to Maturity (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Securities available for sale:
Amortized Cost	$461,630,000	$594,018,000
Gross Unrealized Gains	2,405,000	2,423,000
Gross Unrealized Losses	741,000	45,377,000
Fair Value	463,294,000	551,064,000
Weighted-average yield (as a percent)	2.62%	2.65%
Gross gains recognized on sales of securities		1,200,000	90,200,000
Impairment charges	0	0	200,000
Securities held to maturity:
Amortized Cost	214,454,000	19,912,000
Gross Unrealized Gains	7,988,000	0
Gross Unrealized Losses	109,000	0
Fair Value	222,333,000	19,912,000
Weighted-average yield (as a percent)	2.64%	3.43%
Impairment charge on held to maturity securities	100,000	200,000	900,000
Unrealized holding loss on the transferred securities retained in accumulated other comprehensive income	16,000,000	300,000
Mortgage-backed securities:
Securities available for sale:
Securities available for sale pledged as collateral	8,200,000	14,700,000
Securities held to maturity:
Value of available for sale mortgage-backed securities transferred to held to maturity	191,700,000	9,300,000
U.S. Government sponsored enterprises and federal agencies
Securities available for sale:
Amortized Cost	461,575,000	592,283,000
Gross Unrealized Gains	2,405,000	1,131,000
Gross Unrealized Losses	741,000	45,377,000
Fair Value	463,239,000	548,037,000
Securities held to maturity:
Amortized Cost	209,538,000	14,610,000
Gross Unrealized Gains	7,988,000	0
Gross Unrealized Losses	109,000	0
Fair Value	217,417,000	14,610,000
Mortgage-backed securities, Other
Securities available for sale:
Amortized Cost	55,000	93,000
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	55,000	93,000
Other securities
Securities available for sale:
Amortized Cost	0	1,642,000
Gross Unrealized Gains	0	1,292,000
Gross Unrealized Losses	0	0
Fair Value	0	2,934,000
Securities held to maturity:
Amortized Cost	4,916,000	5,302,000	5,700,000
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	$4,916,000	$5,302,000

Securities_Available_for_Sale_3

Securities Available for Sale and Securities Held to Maturity (Details 2) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Gross unrealized losses and fair value of securities available for sale that is in a loss position
Less than 12 months, Fair Value	$0	$353,449,000
Less than 12 months, Unrealized Losses	0	22,678,000
12 months or more, Fair Value	198,550,000	156,472,000
12 months or more, Unrealized Losses	741,000	22,699,000
Total, fair value	198,550,000	509,921,000
Total, Unrealized Losses	741,000	45,377,000
Gross unrealized losses and fair value of securities held to maturity that is in a loss position
Less than 12 months, Fair Value	2,602,000
Less than 12 months, Unrealized Losses	109,000
12 months or more, Fair Value	0
12 months or more, Unrealized Losses	0
Total, fair value	2,602,000
Total, Unrealized Losses	109,000	0
U.S. Government sponsored enterprises and federal agencies
Gross unrealized losses and fair value of securities available for sale that is in a loss position
Less than 12 months, Fair Value	0	353,449,000
Less than 12 months, Unrealized Losses	0	22,678,000
12 months or more, Fair Value	198,550,000	156,472,000
12 months or more, Unrealized Losses	741,000	22,699,000
Total, fair value	198,550,000	509,921,000
Total, Unrealized Losses	741,000	45,377,000
Gross unrealized losses and fair value of securities held to maturity that is in a loss position
Less than 12 months, Fair Value	2,602,000
Less than 12 months, Unrealized Losses	109,000
12 months or more, Fair Value	0
12 months or more, Unrealized Losses	0
Total, fair value	2,602,000
Total, Unrealized Losses	$109,000

Securities_Available_for_Sale_4

Securities Available for Sale and Securities Held to Maturity (Details 3) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Amortized Cost
Due in one year or less	$4	$0
Due in 1-5 years	76	138
Due in 5-10 years	86,806	24,328
Due after 10 years	374,744	567,910
No stated maturity	0	1,642
Total securities available for sale	461,630	594,018
Fair Value
Due in one year or less	4	0
Due in 1-5 years	76	140
Due in 5-10 years	87,594	24,543
Due after 10 years	375,620	523,447
No stated maturity	0	2,934
Fair Value	463,294	551,064
Yield
Due in one year or less (as a percent)	11.63%	0.00%
Due in 1-5 years (as a percent)	4.53%	5.24%
Due in 5-10 years (as a percent)	1.93%	2.17%
Due after 10 years (as a percent)	2.78%	2.67%
No stated maturity (as a percent)	0.00%	0.00%
Weighted-average yield (as a percent)	2.62%	2.65%
Amortized cost
Due in one year or less	500	0
Due in 1-5 years	2,500	3,000
Due in 5-10 years	400	0
Due after 10 years	211,054	16,912
Amortized Cost	214,454	19,912
Fair Value
Due in one year or less	500	0
Due in 1-5 years	2,500	3,000
Due in 5-10 years	400	0
Due after 10	218,933	16,912
Fair Value	$222,333	$19,912
Yield
Due in one year or less (as a percent)	2.00%	0.00%
Due in 1-5 years (as a percent)	3.08%	2.90%
Due in 5-10 years (as a percent)	3.00%	0.00%
Due after 10 (as a percent)	2.64%	3.52%
Weighted-average yield (as a percent)	2.64%	3.43%

Loans_and_Leases_Details

Loans and Leases (Details) (USD $)	1 Months Ended	12 Months Ended		3 Months Ended
	Jul. 31, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2014
Financing Receivable, Modifications [Line Items]
Loans and minimum lease payments receivables sold		$66,900,000	$60,300,000
Net (loss) gain recognized on sale of loans and minimum lease payments receivables		400,000	500,000
HELOCs
HELOCs included in consumer real estate junior lien portfolio		2,100,000,000	2,100,000,000	2,100,000,000
Amortizing junior lien mortgage loans included in consumer real estate junior lien portfolio		424,400,000	505,500,000	424,400,000
Portion of HELOCs in initial interest-only draw period		1,300,000,000	1,100,000,000	1,300,000,000
Initial interest-only draw period		10 years
Amortization repayment period		20 years
HELOCs with interest-only revolving draw programs		816,000,000	969,200,000	816,000,000
Loans and Leases Receivable Percentage of Consumer Home Equity Line of Credit with Interest only Revolving Draw Programs Maturing Prior to Specified Period		14.60%		14.60%
Loans and minimum lease payments receivables sold		66,900,000	60,300,000
Net (loss) gain recognized on sale of loans and minimum lease payments receivables		400,000	500,000
Consumer auto loans sold		1,300,000,000	800,000,000
Proceeds from sale of consumer auto loans		1,400,000,000	800,000,000
Gains on sale of consumer auto loans before adjustment		44,700,000	29,700,000
Interest-only strips on consumer auto loans retained		17,900,000	50,700,000
Interest-only strips related to sales of auto loans		48,600,000	64,900,000	48,600,000
Impairment related to auto finance interest-only strips		3,500,000	5,400,000
Contractual recourse liabilities related to consumer auto loans		700,000	1,100,000	700,000
Transfers to consumer auto loan securitization	256,300,000
Proceeds from consumer auto loan securitization	266,700,000
Gain (loss) from consumer auto loan securitization	7,400,000
Consumer auto loans portfolio managed by acquired entity		3,800,000,000	2,400,000,000	3,800,000,000
Consumer real estate loans sold		1,400,000,000	800,000,000
Cash received from sale of consumer real estate loans		1,400,000,000	800,000,000
Gains on sale of consumer real estate loans before adjustment		34,100,000	21,700,000
Amount of interest only strips on consumer real estate loans retained		10,800,000	22,200,000
Interest-only strips for consumer real estate loans		21,200,000	19,600,000	21,200,000
Impairment related to consumer real estate interest-only strips		0	500,000
Contractual recourse liabilities related to consumer real estate loans		600,000	600,000	600,000
Consumer real estate loan managed portfolio		7,100,000,000	7,000,000,000	7,100,000,000
Cash received on loans and minimum lease payments receivables sold		68,200,000	62,100,000
Servicing liabilities related to sales of loans and minimum lease payment receivables		800,000	1,300,000
Servicing liabilities related to leasing and equipment finance		1,500,000	1,700,000	1,500,000
Lease residuals related to sales of outstanding minimum lease payments receivables		14,200,000	15,200,000	14,200,000
Leasing and equipment finance loan managed portfolio		4,000,000,000	3,700,000,000	4,000,000,000
Minimum
HELOCs
Draw period for the HELOCs		5 years
Maximum
HELOCs
Draw period for the HELOCs		40 years
Consumer real estate
Financing Receivable, Modifications [Line Items]
Loans and minimum lease payments receivables sold				405,900,000
Proceeds from sale of finance receivables				314,000,000
Net (loss) gain recognized on sale of loans and minimum lease payments receivables				-4,800,000
HELOCs
Loans and minimum lease payments receivables sold				405,900,000
Net (loss) gain recognized on sale of loans and minimum lease payments receivables				($4,800,000)

Loans_and_Leases_Details_1

Loans and Leases (Details 1) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Receivables [Abstract]
Sales of Commercial Loans		$86,500,000
Gain (Loss) on Sales of Commercial Loans		1,600,000
Consumer real estate:
First mortgage lien	3,139,152,000	3,766,421,000
First mortgage lien, Percent Change	-16.70%
Junior lien	2,543,212,000	2,572,905,000
Junior lien, Percent Change	-1.20%
Total consumer real estate	5,682,364,000	6,339,326,000
Total consumer real estate, Percent Change	-10.40%
Commercial real estate:
Permanent	2,382,144,000	2,604,673,000
Permanent, Percent Change	-8.50%
Construction and development	242,111,000	139,024,000
Construction and development, Percent Change	74.20%
Total commercial real estate	2,624,255,000	2,743,697,000
Total commercial real estate, Percent Change	-4.40%
Commercial business	533,410,000	404,655,000
Commercial business, Percent Change	31.80%
Total commercial	3,157,665,000	3,148,352,000
Total commercial, Percent Change	0.30%
Leasing and equipment finance	3,745,322,000	3,428,755,000
Leasing and equipment finance, Percent Change	9.20%
Inventory finance	1,877,090,000	1,664,377,000
Inventory finance, Percent Change	12.80%
Auto finance	1,915,061,000	1,239,386,000
Auto finance, Percentage Change	54.50%
Other	24,144,000	26,743,000
Other finance, Percent Change	-9.70%
Total loans and leases	16,401,646,000	15,846,939,000
Total loans and leases, Percent Change	3.50%
Unamortized Loan Commitment and Origination Fees and Unamortized Discounts or Premiums	43,400,000	30,300,000
2015	711,813,000
2016	529,282,000
2017	365,547,000
2018	213,241,000
2019	105,650,000
Thereafter	36,949,000
Total	$1,962,482,000

Allowance_for_Loan_and_Lease_L2

Allowance for Loan and Lease Losses and Credit Quality Information (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Allowance for loan and lease losses
Balance, at the beginning of the period	$252,230,000	$267,128,000
Charge-offs	-100,967,000	-149,290,000
Recoveries	21,636,000	22,880,000
Net (charge-offs) recoveries	-79,331,000	-126,410,000
Provision for credit losses	95,737,000	118,368,000	247,443,000
Other	-104,467,000	-6,856,000
Balance, at the end of the period	164,169,000	252,230,000	267,128,000
Transfer of loans to held for sale	95,300,000
Transfer of loans to held for sale, allowance for loan and lease losses	77,000,000
Transfer of loans to held for sale, write-downs	18,300,000
Consumer Real Estate
Allowance for loan and lease losses
Balance, at the beginning of the period	176,030,000	182,013,000
Charge-offs	-63,126,000	-97,508,000
Recoveries	6,867,000	8,644,000
Net (charge-offs) recoveries	-56,259,000	-88,864,000
Provision for credit losses	63,973,000	87,100,000
Other	-98,383,000	-4,219,000
Balance, at the end of the period	85,361,000	176,030,000
Commercial
Allowance for loan and lease losses
Balance, at the beginning of the period	37,467,000	51,575,000
Charge-offs	-8,657,000	-28,944,000
Recoveries	2,887,000	2,770,000
Net (charge-offs) recoveries	-5,770,000	-26,174,000
Provision for credit losses	-259,000	12,515,000
Other	-71,000	-449,000
Balance, at the end of the period	31,367,000	37,467,000
Leasing and Equipment Finance
Allowance for loan and lease losses
Balance, at the beginning of the period	18,733,000	21,037,000
Charge-offs	-7,316,000	-7,277,000
Recoveries	3,705,000	3,968,000
Net (charge-offs) recoveries	-3,611,000	-3,309,000
Provision for credit losses	3,324,000	1,005,000
Other	0	0
Balance, at the end of the period	18,446,000	18,733,000
Inventory Finance
Allowance for loan and lease losses
Balance, at the beginning of the period	8,592,000	7,569,000
Charge-offs	-1,653,000	-1,141,000
Recoveries	826,000	373,000
Net (charge-offs) recoveries	-827,000	-768,000
Provision for credit losses	2,498,000	1,949,000
Other	-243,000	-158,000
Balance, at the end of the period	10,020,000	8,592,000
Auto Finance
Allowance for loan and lease losses
Balance, at the beginning of the period	10,623,000	4,136,000
Charge-offs	-11,856,000	-5,305,000
Recoveries	1,491,000	607,000
Net (charge-offs) recoveries	-10,365,000	-4,698,000
Provision for credit losses	23,742,000	13,215,000
Other	-5,770,000	-2,030,000
Balance, at the end of the period	18,230,000	10,623,000
Other
Allowance for loan and lease losses
Balance, at the beginning of the period	785,000	798,000
Charge-offs	-8,359,000	-9,115,000
Recoveries	5,860,000	6,518,000
Net (charge-offs) recoveries	-2,499,000	-2,597,000
Provision for credit losses	2,459,000	2,584,000
Other	0	0
Balance, at the end of the period	$745,000	$785,000

Allowance_for_Loan_and_Lease_L3

Allowance for Loan and Lease Losses and Credit Quality Information (Details 2) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Allowance for loan and lease losses:
Collectively evaluated for impairment	$128,485	$120,153
Individually evaluated for impairment	35,684	132,077
Total	164,169	252,230	267,128
Loans and leases outstanding:
Collectively evaluated for impairment	16,041,606	14,980,436
Individually evaluated for impairment	359,783	865,296
Loans acquired with deteriorated credit quality	257	1,207
Total loans and leases	16,401,646	15,846,939
Consumer Real Estate
Allowance for loan and lease losses:
Collectively evaluated for impairment	57,167	54,449
Individually evaluated for impairment	28,194	121,581
Total	85,361	176,030	182,013
Loans and leases outstanding:
Collectively evaluated for impairment	5,462,005	5,673,518
Individually evaluated for impairment	220,359	665,808
Loans acquired with deteriorated credit quality	0	0
Total loans and leases	5,682,364	6,339,326
Commercial
Allowance for loan and lease losses:
Collectively evaluated for impairment	27,594	28,994
Individually evaluated for impairment	3,773	8,473
Total	31,367	37,467	51,575
Loans and leases outstanding:
Collectively evaluated for impairment	3,038,378	2,971,308
Individually evaluated for impairment	119,287	177,044
Loans acquired with deteriorated credit quality	0	0
Total loans and leases	3,157,665	3,148,352
Leasing and Equipment Finance
Allowance for loan and lease losses:
Collectively evaluated for impairment	16,310	17,093
Individually evaluated for impairment	2,136	1,640
Total	18,446	18,733	21,037
Loans and leases outstanding:
Collectively evaluated for impairment	3,731,420	3,412,769
Individually evaluated for impairment	13,763	15,139
Loans acquired with deteriorated credit quality	139	847
Total loans and leases	3,745,322	3,428,755
Inventory Finance
Allowance for loan and lease losses:
Collectively evaluated for impairment	9,627	8,308
Individually evaluated for impairment	393	284
Total	10,020	8,592	7,569
Loans and leases outstanding:
Collectively evaluated for impairment	1,874,481	1,657,636
Individually evaluated for impairment	2,609	6,741
Loans acquired with deteriorated credit quality	0	0
Total loans and leases	1,877,090	1,664,377
Auto Finance
Allowance for loan and lease losses:
Collectively evaluated for impairment	17,046	10,528
Individually evaluated for impairment	1,184	95
Total	18,230	10,623	4,136
Loans and leases outstanding:
Collectively evaluated for impairment	1,911,267	1,238,556
Individually evaluated for impairment	3,676	470
Loans acquired with deteriorated credit quality	118	360
Total loans and leases	1,915,061	1,239,386
Other
Allowance for loan and lease losses:
Collectively evaluated for impairment	741	781
Individually evaluated for impairment	4	4
Total	745	785	798
Loans and leases outstanding:
Collectively evaluated for impairment	24,055	26,649
Individually evaluated for impairment	89	94
Loans acquired with deteriorated credit quality	0	0
Total loans and leases	$24,144	$26,743

Allowance_for_Loan_and_Lease_L4

Allowance for Loan and Lease Losses and Credit Quality Information (Details 3) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Accruing and Non-accrual Loans and Leases
Current-59 Days Delinquent and Accruing	$16,162,476,000	$15,539,265,000
60-89 Days Delinquent and Accruing	20,426,000	27,806,000
90 Days or More Delinquent and Accruing	2,010,000	2,846,000
Total Accruing	16,184,912,000	15,569,917,000
Non-accrual	216,734,000	277,022,000
Total loans and leases	16,401,646,000	15,846,939,000
Amount that interest income would have been reduced by if accrual was discontinued upon bankruptcy notification	400,000	900,000
Interest income recognized on loans and leases in non-accrual status and contractual interest that would have been recorded had the loans and leases performed in accordance with their original contractual terms
Contractual interest due on non-accrual loans and leases	26,584,000	33,046,000	39,232,000
Interest income recognized on loans and leases in non-accrual status	9,359,000	12,149,000	9,401,000
Foregone interest income	17,225,000	20,897,000	29,831,000
Financing receivables
Accruing and Non-accrual Loans and Leases
Current-59 Days Delinquent and Accruing	16,160,459,000	15,531,395,000
60-89 Days Delinquent and Accruing	20,343,000	27,792,000
90 Days or More Delinquent and Accruing	2,005,000	2,841,000
Total Accruing	16,182,807,000	15,562,028,000
Non-accrual	216,734,000	277,022,000
Total loans and leases	16,399,541,000	15,839,050,000
Consumer Real Estate
Accruing and Non-accrual Loans and Leases
Current-59 Days Delinquent and Accruing	5,493,632,000	6,095,867,000
60-89 Days Delinquent and Accruing	15,267,000	23,347,000
90 Days or More Delinquent and Accruing	194,000	1,079,000
Total Accruing	5,509,093,000	6,120,293,000
Non-accrual	173,271,000	219,033,000
Total loans and leases	5,682,364,000	6,339,326,000
First mortgage lien
Accruing and Non-accrual Loans and Leases
Current-59 Days Delinquent and Accruing	2,987,992,000	3,564,716,000
60-89 Days Delinquent and Accruing	13,176,000	19,815,000
90 Days or More Delinquent and Accruing	194,000	1,079,000
Total Accruing	3,001,362,000	3,585,610,000
Non-accrual	137,790,000	180,811,000
Total loans and leases	3,139,152,000	3,766,421,000
Junior lien
Accruing and Non-accrual Loans and Leases
Current-59 Days Delinquent and Accruing	2,505,640,000	2,531,151,000
60-89 Days Delinquent and Accruing	2,091,000	3,532,000
90 Days or More Delinquent and Accruing	0	0
Total Accruing	2,507,731,000	2,534,683,000
Non-accrual	35,481,000	38,222,000
Total loans and leases	2,543,212,000	2,572,905,000
Consumer real estate loans to customers in bankruptcy
Accruing and Non-accrual Loans and Leases
Current-59 Days Delinquent and Accruing	47,731,000	65,321,000
Non-accrual	12,284,000	13,475,000
Total loans and leases	60,262,000	79,478,000
Total commercial
Accruing and Non-accrual Loans and Leases
Current-59 Days Delinquent and Accruing	3,132,630,000	3,106,383,000
60-89 Days Delinquent and Accruing	0	1,076,000
90 Days or More Delinquent and Accruing	0	354,000
Total Accruing	3,132,630,000	3,107,813,000
Non-accrual	25,035,000	40,539,000
Total loans and leases	3,157,665,000	3,148,352,000
Commercial real estate
Accruing and Non-accrual Loans and Leases
Current-59 Days Delinquent and Accruing	2,599,701,000	2,706,633,000
60-89 Days Delinquent and Accruing	0	886,000
90 Days or More Delinquent and Accruing	0	0
Total Accruing	2,599,701,000	2,707,519,000
Non-accrual	24,554,000	36,178,000
Total loans and leases	2,624,255,000	2,743,697,000
Commercial business
Accruing and Non-accrual Loans and Leases
Current-59 Days Delinquent and Accruing	532,929,000	399,750,000
60-89 Days Delinquent and Accruing	0	190,000
90 Days or More Delinquent and Accruing	0	354,000
Total Accruing	532,929,000	400,294,000
Non-accrual	481,000	4,361,000
Total loans and leases	533,410,000	404,655,000
Leasing and equipment finance
Accruing and Non-accrual Loans and Leases
Current-59 Days Delinquent and Accruing	3,728,115,000	3,404,346,000
60-89 Days Delinquent and Accruing	2,242,000	2,226,000
90 Days or More Delinquent and Accruing	307,000	613,000
Total Accruing	3,730,664,000	3,407,185,000
Non-accrual	12,670,000	14,041,000
Total loans and leases	3,743,334,000	3,421,226,000
Inventory Finance
Accruing and Non-accrual Loans and Leases
Current-59 Days Delinquent and Accruing	1,874,933,000	1,661,798,000
60-89 Days Delinquent and Accruing	49,000	29,000
90 Days or More Delinquent and Accruing	26,000	21,000
Total Accruing	1,875,008,000	1,661,848,000
Non-accrual	2,082,000	2,529,000
Total loans and leases	1,877,090,000	1,664,377,000
Auto Finance
Accruing and Non-accrual Loans and Leases
Current-59 Days Delinquent and Accruing	1,907,005,000	1,236,678,000
60-89 Days Delinquent and Accruing	2,785,000	1,105,000
90 Days or More Delinquent and Accruing	1,478,000	773,000
Total Accruing	1,911,268,000	1,238,556,000
Non-accrual	3,676,000	470,000
Total loans and leases	1,914,944,000	1,239,026,000
Other
Accruing and Non-accrual Loans and Leases
Current-59 Days Delinquent and Accruing	24,144,000	26,323,000
60-89 Days Delinquent and Accruing	0	9,000
90 Days or More Delinquent and Accruing	0	1,000
Total Accruing	24,144,000	26,333,000
Non-accrual	0	410,000
Total loans and leases	24,144,000	26,743,000
Portfolios acquired with deteriorated credit quality
Accruing and Non-accrual Loans and Leases
Current-59 Days Delinquent and Accruing	2,017,000	7,870,000
60-89 Days Delinquent and Accruing	83,000	14,000
90 Days or More Delinquent and Accruing	5,000	5,000
Total Accruing	2,105,000	7,889,000
Non-accrual	0	0
Total loans and leases	$2,105,000	$7,889,000

Allowance_for_Loan_and_Lease_L5

Allowance for Loan and Lease Losses and Credit Quality Information (Details 4) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Accruing and Non-accrual Loans and Leases
Current-59 Days Delinquent and Accruing	$16,162,476	$15,539,265
Non-accrual	216,734	277,022
Total loans and leases	16,401,646	15,846,939
Consumer real estate loans to customers in bankruptcy
Accruing and Non-accrual Loans and Leases
Current-59 Days Delinquent and Accruing	47,731	65,321
60 Plus Days Delinquent and Accruing	247	682
Non-accrual	12,284	13,475
Total loans and leases	$60,262	$79,478

Allowance_for_Loan_and_Lease_L6

Allowance for Loan and Lease Losses and Credit Quality Information (Details 5) (USD $)	3 Months Ended	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	$298.50	$298.50	$796.50
Total Accruing TDR Loans	193.8	193.8	632.8
Loans and minimum lease payments receivables sold		66.9	60.3
Additional funds committed to consumer real estate and commercial loans classified as TDRs	3.9	3.9	6.1
Minimum period for loans to be delinquent to be considered in default		90 days	90 days
Minimum period to be considered for related third-party first mortgage liens to be past due before Junior lien loans are placed on non-accrual status		90 days
Consumer real estate
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	199.6	199.6	641.1
Total Accruing TDR Loans	111.9	111.9	506.6
Loans and minimum lease payments receivables sold	405.9
Average yield on TDR loans (as a percent)		3.30%	3.30%	3.70%
Contractual average rate of TDR loans (as a percent)		6.80%	6.90%	6.90%
Reserves for losses on accruing loan TDRs	20.4	20.4	103.3
Reserves for losses on accruing loan TDRs (as a percent)	18.20%	18.20%	20.40%
Assumed remaining re-default rate used in determining impairment, low end of range (as a percent)	4.00%	4.00%	6.00%
Assumed remaining re-default rate used in determining impairment, high end of range (as a percent)	22.00%	22.00%	25.00%
Percent of accruing TDR loans more than 60 days delinquent	2.40%	2.40%	1.40%
Delinquency period of performing loans and leases		60 days	60 days
Minimum period to be considered for related third-party first mortgage liens to be past due before Junior lien loans are placed on non-accrual status		90 days	90 days
Portion of non-accrual TDR balance, loans discharged in Chapter 7 bankruptcy that are not reaffirmed	50	50	81.5
Portion of non-accrual TDR balance, loans discharged in Chapter 7 bankruptcy that are not reaffirmed (as a percent)	57.00%	57.00%	60.60%
Portion of non-accrual TDR balance, loans discharged in Chapter 7 bankruptcy that are not reaffirmed, current (as a percent)	68.40%	68.40%	71.80%
Commercial
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Recorded Investment	91.6	91.6	147.1
Total Accruing TDR Loans	80.4	80.4	120.9
Loans Removed from Troubled Debt Restructurings Status		12.8	17.1
Reserves for losses on accruing loan TDRs	1.4	1.4	6.3
Reserves for losses on accruing loan TDRs (as a percent)	1.70%	1.70%	5.20%
Delinquency period of performing loans and leases		60 days	60 days
Accruing TDR loans 60 days or more delinquent			1
Accruing TDR loans 60 days or more delinquent, loan balance			0.9
First mortgage lien
Financing Receivable, Modifications [Line Items]
Foregone Interest Income		16.7	17.6	13.9
Junior lien
Financing Receivable, Modifications [Line Items]
Foregone Interest Income		$1.20	$1.20	0.9

Allowance_for_Loan_and_Lease_L7

Allowance for Loan and Lease Losses and Credit Quality Information (Details 6) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Allowance for Loan and Lease Losses and Credit Quality Information
Minimum period for loans to be delinquent to be considered in default	90 days	90 days
Financing Receivable, Modifications [Line Items]
Loan Balance	$7,747	$20,878
Balance of loans modified in the applicable period	177,674	374,761
Defaulted modified loans as a percent of total loans in the applicable period	4.40%	5.60%
Consumer Real Estate
Financing Receivable, Modifications [Line Items]
Loan Balance	3,333	14,989
First mortgage lien
Financing Receivable, Modifications [Line Items]
Loan Balance	1,969	12,510
Junior lien
Financing Receivable, Modifications [Line Items]
Loan Balance	1,364	2,479
Commercial real estate
Financing Receivable, Modifications [Line Items]
Loan Balance	3,895	5,561
Commercial business
Financing Receivable, Modifications [Line Items]
Loan Balance	127	0
Commercial
Financing Receivable, Modifications [Line Items]
Loan Balance	4,022	5,561
Leasing and equipment finance
Financing Receivable, Modifications [Line Items]
Loan Balance	0	268
Auto Finance
Financing Receivable, Modifications [Line Items]
Loan Balance	392	59
Other
Financing Receivable, Modifications [Line Items]
Loan Balance	$0	$1

Allowance_for_Loan_and_Lease_L8

Allowance for Loan and Lease Losses and Credit Quality Information (Details 7) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Impaired Loans
Unpaid Contractual Balance	$399,316	$943,455
Loan Balance	319,659	818,080
Related Allowance Recorded	34,378	130,404
Average Balance	568,870	875,740
Interest Income Recognized	27,517	31,995
Impaired loans with an allowance recorded
Impaired Loans
Unpaid Contractual Balance	251,291	749,262
Loan Balance	224,535	685,342
Related Allowance Recorded	34,378	130,404
Average Balance	454,938	660,509
Interest Income Recognized	20,718	24,628
Impaired loans with an allowance recorded | Consumer real estate
Impaired Loans
Unpaid Contractual Balance	179,939	639,045
Loan Balance	157,073	593,796
Related Allowance Recorded	27,567	120,830
Average Balance	375,435	538,984
Interest Income Recognized	18,207	21,025
Impaired loans with an allowance recorded | First mortgage lien
Impaired Loans
Unpaid Contractual Balance	114,526	553,736
Loan Balance	101,668	521,248
Related Allowance Recorded	18,140	107,841
Average Balance	311,458	481,292
Interest Income Recognized	14,715	17,263
Impaired loans with an allowance recorded | Junior lien
Impaired Loans
Unpaid Contractual Balance	65,413	85,309
Loan Balance	55,405	72,548
Related Allowance Recorded	9,427	12,989
Average Balance	63,977	57,692
Interest Income Recognized	3,492	3,762
Impaired loans with an allowance recorded | Total commercial
Impaired Loans
Unpaid Contractual Balance	58,175	94,768
Loan Balance	54,430	76,165
Related Allowance Recorded	3,773	8,474
Average Balance	65,298	109,237
Interest Income Recognized	2,349	3,263
Impaired loans with an allowance recorded | Commercial real estate
Impaired Loans
Unpaid Contractual Balance	58,157	84,851
Loan Balance	54,412	71,785
Related Allowance Recorded	3,772	7,594
Average Balance	63,099	99,177
Interest Income Recognized	2,349	3,193
Impaired loans with an allowance recorded | Commercial business
Impaired Loans
Unpaid Contractual Balance	18	9,917
Loan Balance	18	4,380
Related Allowance Recorded	1	880
Average Balance	2,199	10,060
Interest Income Recognized	0	70
Impaired loans with an allowance recorded | Leasing and Equipment Finance
Impaired Loans
Unpaid Contractual Balance	8,257	8,238
Loan Balance	8,257	8,238
Related Allowance Recorded	1,457	717
Average Balance	8,247	7,954
Interest Income Recognized	58	174
Impaired loans with an allowance recorded | Inventory Finance
Impaired Loans
Unpaid Contractual Balance	1,754	6,741
Loan Balance	1,758	6,741
Related Allowance Recorded	393	284
Average Balance	4,249	4,114
Interest Income Recognized	97	158
Impaired loans with an allowance recorded | Auto Finance
Impaired Loans
Unpaid Contractual Balance	3,074	373
Loan Balance	2,928	308
Related Allowance Recorded	1,184	95
Average Balance	1,617	154
Interest Income Recognized	0	2
Impaired loans with an allowance recorded | Other
Impaired Loans
Unpaid Contractual Balance	92	97
Loan Balance	89	94
Related Allowance Recorded	4	4
Average Balance	92	66
Interest Income Recognized	7	6
Impaired loans without an allowance recorded
Impaired Loans
Unpaid Contractual Balance	148,025	194,193
Loan Balance	95,124	132,738
Average Balance	113,932	215,231
Interest Income Recognized	6,799	7,367
Impaired loans without an allowance recorded | Consumer real estate
Impaired Loans
Unpaid Contractual Balance	87,402	85,943
Loan Balance	42,545	47,331
Average Balance	44,938	107,504
Interest Income Recognized	3,606	3,987
Impaired loans without an allowance recorded | First mortgage lien
Impaired Loans
Unpaid Contractual Balance	53,606	59,233
Loan Balance	35,147	43,025
Average Balance	39,086	92,268
Interest Income Recognized	2,321	2,305
Impaired loans without an allowance recorded | Junior lien
Impaired Loans
Unpaid Contractual Balance	33,796	26,710
Loan Balance	7,398	4,306
Average Balance	5,852	15,236
Interest Income Recognized	1,285	1,682
Impaired loans without an allowance recorded | Total commercial
Impaired Loans
Unpaid Contractual Balance	58,291	107,933
Loan Balance	50,980	85,245
Average Balance	68,113	107,595
Interest Income Recognized	3,067	3,380
Impaired loans without an allowance recorded | Commercial real estate
Impaired Loans
Unpaid Contractual Balance	57,809	102,523
Loan Balance	50,500	79,833
Average Balance	65,167	101,921
Interest Income Recognized	2,973	3,165
Impaired loans without an allowance recorded | Commercial business
Impaired Loans
Unpaid Contractual Balance	482	5,410
Loan Balance	480	5,412
Average Balance	2,946	5,674
Interest Income Recognized	94	215
Impaired loans without an allowance recorded | Inventory Finance
Impaired Loans
Unpaid Contractual Balance	848
Loan Balance	851
Average Balance	426	0
Interest Income Recognized	126	0
Impaired loans without an allowance recorded | Auto Finance
Impaired Loans
Unpaid Contractual Balance	1,484	317
Loan Balance	748	162
Average Balance	455	132
Interest Income Recognized	$0	$0

Premises_and_Equipment_Details

Premises and Equipment (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Premises and equipment
Subtotal	$795,943,000	$779,677,000
Less accumulated depreciation and amortization	359,582,000	342,075,000
Premises and equipment, net	436,361,000	437,602,000
Operating leases
Net lease expense including utilities and other operating expenses	34,000,000	35,400,000	35,500,000
Future minimum rental payments for operating leases
2015	26,894,000
2016	29,592,000
2017	28,201,000
2018	26,355,000
2019	15,199,000
Thereafter	67,030,000
Total	193,271,000
Land
Premises and equipment
Subtotal	152,418,000	154,136,000
Office buildings
Premises and equipment
Subtotal	276,943,000	277,085,000
Leasehold improvements
Premises and equipment
Subtotal	53,954,000	54,069,000
Furniture and equipment
Premises and equipment
Subtotal	$312,628,000	$294,387,000

Goodwill_and_Other_Intangible_2

Goodwill and Other Intangible Assets (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Amortizable intangible assets:
Gross Amount	$10,669,000	$10,669,000
Accumulated Amortization	6,028,000	4,343,000
Net Amount	4,641,000	6,326,000
Amortization expenses	1,700,000	2,300,000	1,500,000
Goodwill	225,640,000	225,640,000
Estimated amortization expense for intangible assets
2015	1,600,000
2016	1,400,000
2017	500,000
2018	400,000
2019	300,000
Impairment of goodwill	0	0	0
Impairment of intangible assets	0	0	0
Funding
Amortizable intangible assets:
Goodwill	141,245,000	141,245,000
Lending
Amortizable intangible assets:
Goodwill	84,395,000	84,395,000
Deposit base intangibles
Amortizable intangible assets:
Gross Amount	3,049,000	3,049,000
Accumulated Amortization	1,502,000	1,105,000
Net Amount	1,547,000	1,944,000
Customer base intangibles
Amortizable intangible assets:
Gross Amount	2,730,000	2,730,000
Accumulated Amortization	1,377,000	996,000
Net Amount	1,353,000	1,734,000
Non-compete agreements
Amortizable intangible assets:
Gross Amount	4,590,000	4,590,000
Accumulated Amortization	2,849,000	1,942,000
Net Amount	1,741,000	2,648,000
Tradename
Amortizable intangible assets:
Gross Amount	300,000	300,000
Accumulated Amortization	300,000	300,000
Net Amount	$0	$0

Deposits_Details

Deposits (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Weighted Average Rate
Interest bearing checking weighted average rate (as a percent)	0.04%	0.06%
Total checking weighted average rate (as a percent)	0.02%	0.03%
Savings weighted average rate (as a percent)	0.15%	0.20%
Money market weighted average rate (as a percent)	0.54%	0.29%
Total checking, savings and money market weighted average rate (as a percent)	0.13%	0.14%
Certificates of deposit weighted average rate (as a percent)	0.78%	0.86%
Total deposits weighted average rate (as a percent)	0.26%	0.26%
Deposits
Non-interest bearing checking	$2,832,526	$2,642,600
Interest bearing checking	2,362,717	2,337,851
Total checking	5,195,243	4,980,451
Savings	5,212,320	6,194,003
Money market	1,993,130	831,910
Total checking, savings and money market	12,400,693	12,006,364
Certificates of deposit	3,049,189	2,426,412
Total deposits	15,449,882	14,432,776
% of Total
Non-interest bearing checking as a percent of total deposits	18.30%	18.30%
Interest bearing checking as a percent of total deposits	15.30%	16.20%
Total checking as a percent of total deposits	33.60%	34.50%
Savings as a percent of total deposits	33.70%	42.90%
Money market as a percent of total deposits	13.00%	5.80%
Total checking, savings and money market as a percent of total deposits	80.30%	83.20%
Certificates of deposit as a percent of total deposits	19.70%	16.80%
Total deposits as a percent of total deposits	100.00%	100.00%
Certificates of deposit remaining maturities, Denominations $100 Thousand or Greater
0 - 3 months	250,200
4 - 6 months	150,195
7 - 12 months	345,161
13 - 24 months	505,991
Over 24 months	75,609
Total	1,327,156
Certificates of deposit remaining maturities, Denominations Less Than $100 Thousand
0 - 3 months	348,379
4 - 6 months	244,631
7 - 12 months	491,403
13 - 24 months	587,088
Over 24 months	50,532
Total	1,722,033
Certificates of deposit with remaining maturities, Total
0 - 3 months	598,579
4 - 6 months	394,826
7 - 12 months	836,564
13 - 24 months	1,093,079
Over 24 months	126,141
Total	$3,049,189	$2,426,412

Shortterm_Borrowings_Details

Short-term Borrowings (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Short-term Borrowings
Short-term borrowings	$4,425,000	$4,918,000
Interest rate at period end (as a percent)	0.10%	0.10%
Average daily balances of short-term borrowings	83,673,000	7,685,000
Average daily interest rate (as a percent)	0.31%	0.60%
Mortgage-backed securities
Short-term Borrowings
Fair value of short-term debt	8,200,000	14,700,000
Securities sold under repurchase agreements
Short-term Borrowings
Short-term borrowings	4,425,000	4,918,000
Interest rate at period end (as a percent)	0.10%	0.10%
Average daily balances of short-term borrowings	5,956,000	5,713,000
Average daily interest rate (as a percent)	0.18%	0.18%
Maximum month-end balances of short-term borrowings	4,425,000	7,071,000
Securities sold under repurchase agreements | Mortgage-backed securities
Short-term Borrowings
Fair value of short-term debt	6,800,000
Federal Home Loan Bank advances
Short-term Borrowings
Average daily balances of short-term borrowings	74,385,000	14,000
Average daily interest rate (as a percent)	0.26%	0.34%
Maximum month-end balances of short-term borrowings	250,000,000	0
Federal funds purchased
Short-term Borrowings
Average daily balances of short-term borrowings	375,000	660,000
Average daily interest rate (as a percent)	0.40%	0.34%
Line of Credit - TCF Commercial Finance Canada, Inc.
Short-term Borrowings
Average daily balances of short-term borrowings	2,957,000	1,298,000
Average daily interest rate (as a percent)	1.88%	2.57%
Maximum month-end balances of short-term borrowings	$11,751,000	$9,587,000

Longterm_Borrowings_Details

Long-term Borrowings (Details) (USD $)	0 Months Ended
	Mar. 17, 2014	Dec. 31, 2014	Dec. 31, 2013
Debt instrument
Long-term Debt		$1,232,065,000	$1,483,325,000
Weighted-Average interest rate on long term debt (as a percent)		1.63%	1.41%
Federal Home Loan Bank advances
Debt instrument
Long-term Debt		947,000,000	1,170,000,000
Weighted-Average interest rate on long term debt (as a percent)		0.56%	0.52%
Variable-rate FHLB advances prepayable monthly		375,000,000
Federal Home Loan Bank advances | Maturity year 2014
Debt instrument
Long-term Debt		0	398,000,000
Weighted-Average interest rate on long term debt (as a percent)		0.00%	0.37%
Federal Home Loan Bank advances | Maturity year 2015
Debt instrument
Long-term Debt		125,000,000	200,000,000
Weighted-Average interest rate on long term debt (as a percent)		0.38%	0.33%
Federal Home Loan Bank advances | Maturity year 2016
Debt instrument
Long-term Debt		547,000,000	497,000,000
Weighted-Average interest rate on long term debt (as a percent)		0.75%	0.76%
Federal Home Loan Bank advances | Maturity year 2016 | TCF Bank
Debt instrument
Loans pledged as collateral		5,200,000,000
Federal Home Loan Bank advances | Maturity Year 2017
Debt instrument
Long-term Debt		275,000,000	75,000,000
Weighted-Average interest rate on long term debt (as a percent)		0.25%	0.21%
Subordinated bank notes
Debt instrument
Long-term Debt		184,124,000	233,981,000
Weighted-Average interest rate on long term debt (as a percent)		6.05%	5.15%
Subordinated bank notes | Maturity year 2015
Debt instrument
Long-term Debt		0	50,000,000
Weighted-Average interest rate on long term debt (as a percent)		0.00%	1.83%
Subordinated bank notes | Maturity year 2015 | TCF Bank
Debt instrument
Redemption of debt	50,000,000
Subordinated bank notes | Maturity year 2016
Debt instrument
Long-term Debt		74,930,000	74,868,000
Weighted-Average interest rate on long term debt (as a percent)		5.59%	5.59%
Fixed interest rate (as a percent)		5.50%
Subordinated bank notes | Maturity Year 2022
Debt instrument
Long-term Debt		109,194,000	109,113,000
Weighted-Average interest rate on long term debt (as a percent)		6.37%	6.37%
Fixed interest rate (as a percent)		6.25%
Discounted lease rentals
Debt instrument
Long-term Debt		92,887,000	68,506,000
Weighted-Average interest rate on long term debt (as a percent)		3.85%	3.94%
Discounted lease rentals | Maturity year 2014
Debt instrument
Long-term Debt		0	26,275,000
Weighted-Average interest rate on long term debt (as a percent)		0.00%	4.06%
Discounted lease rentals | Maturity year 2015
Debt instrument
Long-term Debt		32,904,000	18,866,000
Weighted-Average interest rate on long term debt (as a percent)		3.84%	3.96%
Discounted lease rentals | Maturity year 2016
Debt instrument
Long-term Debt		27,539,000	13,319,000
Weighted-Average interest rate on long term debt (as a percent)		3.83%	3.92%
Discounted lease rentals | Maturity Year 2017
Debt instrument
Long-term Debt		20,580,000	8,281,000
Weighted-Average interest rate on long term debt (as a percent)		3.82%	3.69%
Discounted lease rentals | Maturity Year 2018
Debt instrument
Long-term Debt		9,032,000	1,689,000
Weighted-Average interest rate on long term debt (as a percent)		3.92%	3.45%
Discounted lease rentals | Maturity Year 2019
Debt instrument
Long-term Debt		2,589,000	76,000
Weighted-Average interest rate on long term debt (as a percent)		4.23%	3.31%
Discounted lease rentals | Maturity Year 2020
Debt instrument
Long-term Debt		160,000	0
Weighted-Average interest rate on long term debt (as a percent)		4.57%	0.00%
Discounted lease rentals | Maturity Year 2021
Debt instrument
Long-term Debt		83,000	0
Weighted-Average interest rate on long term debt (as a percent)		4.57%	0.00%
Other long-term
Debt instrument
Long-term Debt		8,054,000	10,838,000
Weighted-Average interest rate on long term debt (as a percent)		1.36%	1.36%
Other long-term | Maturity year 2014
Debt instrument
Long-term Debt		0	2,718,000
Weighted-Average interest rate on long term debt (as a percent)		0.00%	1.36%
Other long-term | Maturity year 2015
Debt instrument
Long-term Debt		2,670,000	2,669,000
Weighted-Average interest rate on long term debt (as a percent)		1.36%	1.36%
Other long-term | Maturity year 2016
Debt instrument
Long-term Debt		2,642,000	2,705,000
Weighted-Average interest rate on long term debt (as a percent)		1.36%	1.36%
Other long-term | Maturity Year 2017
Debt instrument
Long-term Debt		$2,742,000	$2,746,000
Weighted-Average interest rate on long term debt (as a percent)		1.36%	1.36%

Income_Taxes_Details

Income Taxes (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Current
Federal	$55,062,000	($38,206,000)	$6,646,000
State	2,087,000	7,686,000	7,994,000
Foreign	5,185,000	3,939,000
Total current	62,334,000	-26,581,000	14,640,000
Deferred
Federal	26,308,000	107,630,000	-129,082,000
State	11,147,000	3,941,000	-18,416,000
Foreign	-23,000	-645,000
Total deferred	37,432,000	110,926,000	-147,498,000
Total
Federal, Total	81,370,000	69,424,000	-122,436,000
State, Total	13,234,000	11,627,000	-10,422,000
Foreign, Total	5,162,000	3,294,000
Total	99,766,000	84,345,000	-132,858,000
Reconciliation of effective income tax rate from the federal income tax rate
Federal income tax rate (as a percent)	35.00%	35.00%	35.00%
Increase (decrease) resulting from:
State income tax, net of federal income tax (as a percent)	3.06%	3.11%	1.99%
Non-controlling interest tax effect (as a percent)	-0.92%	-1.01%	0.64%
Tax exempt income (as a percent)	-0.76%	-0.86%	0.55%
Foreign tax effects (as a percent)	-0.58%	-1.13%	0.00%
Deferred tax adjustments (as a percent)	-0.33%	-0.30%	1.40%
Civil money penalty (as a percent)	0.00%	0.00%	-1.03%
Other, net (as a percent)	-0.01%	-0.11%	0.58%
Effective income tax rate (as a percent)	35.46%	34.70%	39.13%
Deferred tax benefit related to undistributed foreign earnings		1,200,000
Undistributed foreign earnings	48,100,000	33,500,000
Potential deferred tax liability	4,000,000	2,700,000
Total amount of unrecognized tax benefits that, if recognized, would affect the tax provision and the effective income tax rate	1,500,000	1,200,000
Interest and penalties, net of tax effects	71,000	110,000	77,000
Accrued interest and penalties	$498,000	$427,000

Income_Taxes_Details_2

Income Taxes (Details 2) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Reconciliation of the change in unrecognized tax benefits
Balance at the beginning of the period	$4,704	$4,230	$2,377
Increases for tax positions related to the current year	468	394	449
Increases for tax positions related to prior years	8	362	1,781
Decreases for tax positions related to prior years	-350	-67	0
Settlements with taxing authorities	0	-39	-70
Decreases related to lapses of applicable statutes of limitation	-181	-176	-307
Balance at the end of the period	4,649	4,704	4,230
Deferred tax assets:
Allowance for loan and lease losses	63,862	62,464
Stock compensation and deferred compensation plans	34,850	29,576
Net operating losses and credit carryforwards	11,649	48,692
Valuation allowance	-5,669	-8,745
Non-accrual interest	9,333	1,911
Securities available-for-sale	5,397	16,301
Accrued expense	4,892	5,203
Other	2,721	6,676
Total deferred tax assets	127,035	162,078
Deferred tax liabilities
Lease financing	299,621	284,767
Premises and equipment	19,114	19,289
Loan fees and discounts	14,921	17,287
Prepaid expenses	12,479	10,526
Goodwill and other intangibles	4,139	4,694
Other	8,106	7,361
Total deferred tax liabilities	358,380	343,924
Net deferred tax liabilities	$231,345	$181,846

Income_Taxes_Details_3

Income Taxes (Details 3) (State, USD $)	Dec. 31, 2014
In Millions, unless otherwise specified
State
Net operating losses and credits carryforwards
Net operating losses carryforwards	$6

Equity_Details

Equity (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Restricted Retained Earnings
Undistributed earnings of TCF's bank subsidiary	$134,400,000
Provision for federal income taxes on appropriated earnings included in retained earnings	0
Treasury Stock and Other
Treasury stock, at cost	-1,102,000	-1,102,000
Shares held in trust for deferred compensation plans, at cost	-48,298,000	-41,096,000
Total	($49,400,000)	($42,198,000)
Common stock repurchased (in shares)	0	0	0
Stock repurchase program, remaining shares authorized for repurchase	5,400,000

Equity_Details_2

Equity (Details 2) (USD $)	12 Months Ended			0 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jun. 25, 2012	Dec. 19, 2012
Public offering of preferred shares
Preferred stock, par value (in dollars per share)	$0.01	$0.01
Cash dividends paid on preferred stock	$19,388,000	$19,065,000	$5,606,000
Series A Preferred Stock
Public offering of preferred shares
Interest in a share of Series A Preferred Stock				0.001
Par value per share				$0.01
Shares issued				6,900,000
Offering price per depository share				$25
Annual rate of dividend (as a percent)				7.50%
Underwriting discounts and commissions and estimated offering expenses				5,800,000
Net proceeds of offering net of underwriting discounts and commissions and estimated offering expenses				166,700,000
Cash dividends paid on preferred stock	12,900,000	12,900,000
Series B Preferred Stock
Public offering of preferred shares
Shares issued					4,000,000
Annual rate of dividend (as a percent)					6.45%
Preferred stock, par value (in dollars per share)					$0.01
Underwriting discounts and commissions and estimated offering expenses					3,500,000
Net proceeds of offering net of underwriting discounts and commissions and estimated offering expenses					96,500,000
Cash dividends paid on preferred stock	$6,500,000	$6,100,000

Equity_Details_3

Equity (Details 3) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Warrants
Outstanding warrants to purchase common stock (in shares)	3,199,988
Warrants exercise price (in dollars per share)	16.93
Joint Venture
Ownership interest in Joint Venture, by TCF (as a percent)	55.00%
Ownership interest in Joint Venture, by Toro Company (as a percent)	45.00%
Directors Deferred Compensation Plan
Deferred Compensation Plans
Fair value of the assets in the plan	$13,800,000	$15,100,000
Directors Deferred Compensation Plan | TCF Common Stock
Deferred Compensation Plans
Fair value of the assets in the plan	8,600,000	9,400,000
Directors Deferred Compensation Plan | Directors | Maximum
Deferred Compensation Plans
Amount of director fees and restricted stock awards which can be deferred by a non-employee director under the deferred compensation plan (as a percent).	100.00%
TCF Employees Deferred Stock Compensation Plan | TCF Common Stock
Deferred Compensation Plans
Fair value of the assets in the plan	33,200,000	30,200,000
TCF Employees Stock Purchase Plan - Supplemental Plan
Deferred Compensation Plans
Matching contributions to the plan	1,500,000	800,000
Fair value of the assets in the plan	31,800,000	27,800,000
Other contributions to the plan, other than payment of administrative expenses	0	0
TCF Employees Stock Purchase Plan - Supplemental Plan | TCF Common Stock
Deferred Compensation Plans
Fair value of the assets in the plan	$18,300,000	$16,400,000
TCF Employees Stock Purchase Plan - Supplemental Plan | Certain employees | Maximum
Deferred Compensation Plans
Employees contribution under supplemental non-qualified Employee Stock Purchase Plan (as a percent)	50.00%

Regulatory_Capital_Requirement2

Regulatory Capital Requirements (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Regulatory Capital Requirements [Abstract]
Number of prior calendar years considered for payment of dividends in excess of net retained profit	2 years
Net profits for the current year combined with retained net profits for preceding two calendar years	$83,700,000
Maximum
Compliance with Regulatory Capital Requirements under Banking Regulations
Percentage of net retained profits for the current year combined with retained net profits for the preceding two calendar years that can be declared as dividend	100.00%
Tier 1 Leverage Capital Ratios
Tier 1 leverage ratio for bank holding companies and banks, scenario 2 (as a percent)	4.00%
Minimum
Tier 1 Leverage Capital Ratios
Tier 1 leverage ratio for bank holding companies and banks, scenario 1 (as a percent)	3.00%
TCF
Tier 1 leverage capital
Actual, Amount	1,919,887,000	1,763,682,000
Minimum Capital Requirement, Amount	762,711,000	726,242,000
Tier 1 risk-based capital
Actual, Amount	1,919,887,000	1,763,682,000
Minimum Capital Requirement, Amount	652,857,000	618,228,000
Well-Capitalized Capital Requirement, Amount	979,286,000	927,342,000
Total risk-based capital
Actual, Amount	2,209,999,000	2,107,981,000
Minimum Capital Requirement, Amount	1,305,714,000	1,236,456,000
Well-Capitalized Capital Requirement, Amount	1,632,143,000	1,545,571,000
Tier 1 Leverage Capital Ratios
Actual, Ratio (as a percent)	10.07%	9.71%
Minimum Capital Requirement, Ratio (as a percent)	4.00%	4.00%
Tier 1 risk-based capital ratios
Actual, Ratio (as a percent)	11.76%	11.41%
Minimum Capital Requirement, Ratio (as a percent)	4.00%	4.00%
Well-Capitalized Capital Requirement, Ratio (as a percent)	6.00%	6.00%
Total risk-based capital ratios
Actual, Ratio (as a percent)	13.54%	13.64%
Minimum Capital Requirement, Ratio (as a percent)	8.00%	8.00%
Well-Capitalized Capital Requirement, Ratio (as a percent)	10.00%	10.00%
TCF Bank
Tier 1 leverage capital
Actual, Amount	1,836,019,000	1,675,082,000
Minimum Capital Requirement, Amount	762,746,000	725,895,000
Well-Capitalized Capital Requirement, Amount	953,432,000	907,368,000
Tier 1 risk-based capital
Actual, Amount	1,836,019,000	1,675,082,000
Minimum Capital Requirement, Amount	652,785,000	618,033,000
Well-Capitalized Capital Requirement, Amount	979,177,000	927,049,000
Total risk-based capital
Actual, Amount	2,126,131,000	2,018,959,000
Minimum Capital Requirement, Amount	1,305,569,000	1,236,066,000
Well-Capitalized Capital Requirement, Amount	$1,631,961,000	$1,545,082,000
Tier 1 Leverage Capital Ratios
Actual, Ratio (as a percent)	9.63%	9.23%
Minimum Capital Requirement, Ratio (as a percent)	4.00%	4.00%
Well-Capitalized Capital Requirement, Ratio (as a percent)	5.00%	5.00%
Tier 1 risk-based capital ratios
Actual, Ratio (as a percent)	11.25%	10.84%
Minimum Capital Requirement, Ratio (as a percent)	4.00%	4.00%
Well-Capitalized Capital Requirement, Ratio (as a percent)	6.00%	6.00%
Total risk-based capital ratios
Actual, Ratio (as a percent)	13.03%	13.07%
Minimum Capital Requirement, Ratio (as a percent)	8.00%	8.00%
Well-Capitalized Capital Requirement, Ratio (as a percent)	10.00%	10.00%

Stock_Compensation_Details

Stock Compensation (Details) (USD $)	12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Share-based compensation
Shares reserved for issuance under the Program	2,754,016
Unrecognized stock compensation expense for restricted stock awards and options	$22,532
Weighted average amortization (years)	2 years 7 months 6 days
Restricted Stock
Share-based compensation
Compensation expense for restricted stock	8,690	10,467	10,934
Unrecognized stock compensation expense for restricted stock awards and options		14,482	19,530
Tax benefit recognized for stock compensation expense	$3,424	$4,034	$4,259
Weighted average amortization (years)		1 year 7 months 6 days	2 years 1 month 6 days
Restricted stock, shares activity
Outstanding at the beginning of the period (in shares)	3,355,295	3,212,235	2,284,114
Granted (in shares)	1,120,750	493,650	1,769,700
Forfeited/cancelled (in shares)	-108,490	-120,313	-322,908
Vested (in shares)	-1,509,061	-230,277	-518,671
Outstanding at the end of the period (in shares)	2,858,494	3,355,295	3,212,235
Restricted Stock, Weighted-Average Grant Date Fair Value
Weighted-Average Grant Date Fair Value, Outstanding at the beginning (in dollars per share)	$11.09	$11.13	$12.95
Weighted-Average Grant Date Fair Value, Granted (in dollars per share)	$15.61	$13.55	$9.27
Weighted-Average Grant Date Fair Value, Forfeited/cancelled (in dollars per share)	$13.06	$12.75	$10.13
Weighted-Average Grant Date Fair Value, Vested (in dollars per share)	$11.21	$16.04	$13.42
Weighted-Average Grant Date Fair Value, Outstanding at the end (in dollars per share)	$12.73	$11.09	$11.13
Restricted Stock | Minimum
Restricted Stock, Grant Date Fair Value Range
Grant Date Fair Value, Outstanding at the beginning (in dollars per share)	$6.16	$6.16	$6.16	$6.16
Grant Date Fair Value, Granted (in dollars per share)	$13.84	$12.47	$7.73
Grant Date Fair Value, Forfeited/canceled (in dollars per share)	$6.80	$9.65	$7.73
Grant Date Fair Value, Vested (in dollars per share)	$8.35	$9.48	$7.57
Grant Date Fair Value, Outstanding at the end (in dollars per share)	$6.16	$6.16	$6.16	$6.16
Restricted Stock | Maximum
Restricted Stock, Grant Date Fair Value Range
Grant Date Fair Value, Outstanding at the beginning (in dollars per share)	$16.02	$15.17	$25.18	$28.64
Grant Date Fair Value, Granted (in dollars per share)	$16.02	$15.17	$11.56
Grant Date Fair Value, Forfeited/canceled (in dollars per share)	$15.79	$17.37	$28.02
Grant Date Fair Value, Vested (in dollars per share)	$14.90	$25.18	$28.64
Grant Date Fair Value, Outstanding at the end (in dollars per share)	$16.02	$15.17	$25.18	$28.64
Performance-based restricted stock
Share-based compensation
Outstanding number of shares to vest only if certain return on asset goals, loan volumes and credit quality metrics, and service conditions are achieved	1,080,916
Employee Stock Option [Member]
Stock options, shares activity
Granted (in shares)	0	0	0
Exercised (in shares)	-47,000
Forfeited/canceled (in shares)	0	-451,104	-121,640
Vested (in shares)	0	0	0
Outstanding at the end of the period (in shares)	1,579,000
Stock Options, Exercise Price Range
Stock Options Outstanding, Weighted-Average Remaining Contractual Life	2 years 11 months 23 days
Weighted-Average Exercise Price
Weighted-Average Exercise Price, Granted (in dollars per share)	$0	$0	$0
Weighted-Average Exercise Price, Exercised (in dollars per share)	$15.75
Weighted-Average Exercise Price, Forfeited/canceled (in dollars per share)	$0	$15.75	$15.75
Weighted-Average Exercise Price, Vested (in dollars per share)	$0	$0	$0
Weighted-Average Exercise Price, Outstanding at the end (in dollars per share)	$13.91
Stock options outstanding and exercisable
Stock Options Exercisable (in shares)	1,579,000
Stock Options Exercisable, Weighted-Average Exercise Price (in dollars per share)	$13.91
Employee Stock Option [Member] | Minimum
Stock Options, Exercise Price Range
Exercise price, Outstanding at the beginning (in dollars per share)	$12.85	$12.85	$12.85	$12.85
Exercise price, Granted (in dollars per share)	$0	$0	$0
Exercise price, Exercised (in dollars per share)	$15.75
Exercise price, Forfeited/canceled (in dollars per share)	$0	$15.75	$15.75
Exercise price, Vested (in dollars per share)	$0	$0	$0
Exercise price, Outstanding at the end (in dollars per share)	$12.85	$12.85	$12.85	$12.85
Stock options outstanding and exercisable
Exercise price, options exercisable (in dollars per share)	$12.85
Employee Stock Option [Member] | Maximum
Stock Options, Exercise Price Range
Exercise price, Outstanding at the beginning (in dollars per share)	$15.75	$15.75	$15.75	$15.75
Exercise price, Granted (in dollars per share)	$0	$0	$0
Exercise price, Exercised (in dollars per share)	$15.75
Exercise price, Forfeited/canceled (in dollars per share)	$0	$15.75	$15.75
Exercise price, Vested (in dollars per share)	$0	$0	$0
Exercise price, Outstanding at the end (in dollars per share)	$15.75	$15.75	$15.75	$15.75
Stock options outstanding and exercisable
Exercise price, options exercisable (in dollars per share)	$15.75
Other Restricted Stock | Minimum
Share-based compensation
Stock options vesting period	1 year
Other Restricted Stock | Maximum
Share-based compensation
Stock options vesting period	5 years
Incentive Stock Program [Member]
Share-based compensation
Stock options, expiration period	10 years
Expected volatility	28.50%
Weighted-average volatility	28.50%
Expected dividend yield	3.50%
Stock options, shares activity
Outstanding at the beginning of the period (in shares)	1,626,000	2,077,104	2,198,744
Outstanding at the end of the period (in shares)		1,626,000	2,077,104	2,198,744
Stock Options, Exercise Price Range
Stock Options Outstanding, Weighted-Average Remaining Contractual Life		4 years 4 months 10 days	4 years 2 months 19 days	5 years 8 months 19 days
Weighted-Average Exercise Price
Weighted-Average Exercise Price, Outstanding at the beginning (in dollars per share)		$14.35	$14.43
Weighted-Average Exercise Price, Outstanding at the end (in dollars per share)			$14.35	$14.43
Stock options outstanding and exercisable
Stock Options Exercisable, Weighted-Average Exercise Price (in dollars per share)		$13.97
Incentive Stock Program [Member] | Minimum
Share-based compensation
Stock options vesting period	1 year
Expected term (years)	6 years 3 months
Risk-free interest rate	2.58%
Incentive Stock Program [Member] | Maximum
Share-based compensation
Stock options vesting period	10 years
Expected term (years)	6 years 9 months
Risk-free interest rate	2.91%

Employee_Benefit_Plans_Details

Employee Benefit Plans (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Employee stock purchase plan
Participants' contribution as a percentage of covered compensation	50.00%
Fair value of the assets in the plan	$244
Employer contribution to the plan	9.6	8.9	8
TCF Common Stock
Employee stock purchase plan
Fair value of the assets in the plan	$139.60
Minimum
Employee stock purchase plan
Employer's contribution, vesting period	5 years
One through four years
Employee stock purchase plan
Employer matching contribution per dollar	0.5
Minimum years of service	1 year
Maximum years of service	4 years
Maximum matching contribution by employer as percentage of covered compensation	3.00%
Five through nine years
Employee stock purchase plan
Employer matching contribution per dollar	0.75
Minimum years of service	5 years
Maximum years of service	9 years
Maximum matching contribution by employer as percentage of covered compensation	4.50%
10 or more years
Employee stock purchase plan
Employer matching contribution per dollar	1
Minimum years of service	10 years
Maximum matching contribution by employer as percentage of covered compensation	6.00%

Employee_Benefit_Plans_Details1

Employee Benefit Plans (Details 2) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Pension Plan
Employee Benefit Plans
Requisite age of employees to be eligible for participation	21 years
Term of treasury note used to determine rate credited to participants' accounts	5 years
Basis spread on variable base rate used to calculate interest on participants' accounts balance (as a percent)	0.25%
Change in benefit obligation
Benefit obligation at beginning of year	$41,870,000	$45,037,000
Interest cost	1,587,000	1,292,000	1,763,000
Actuarial (gain) loss	1,862,000	-2,196,000	289,000
Benefits paid	-5,829,000	-2,263,000
Projected benefit obligation at end of year	39,490,000	41,870,000	45,037,000
Change in fair value of plan assets:
Fair value of plan assets at beginning of year	51,018,000	53,617,000
Actual (loss) on plan assets	511,000	336,000	277,000
Benefits paid	-5,829,000	-2,263,000
TCF contributions	0	0
Fair value of plan assets at end of year	44,678,000	51,018,000	53,617,000
Funded status of plans, end of period	5,188,000	9,148,000
Amounts recognized in the Consolidated Statements of Financial Condition:
Prepaid (accrued) benefit cost at end of year	5,188,000	9,148,000
Prior service cost	0	0
Accumulated other comprehensive income, before tax	0	0
Total recognized asset (liability)	5,188,000	9,148,000
Benefit obligation:
Accumulated benefit obligation	39,500,000	41,900,000
Changes recognized in accumulated other comprehensive loss
Accumulated other comprehensive (income) loss at the beginning of the year, before tax	0
Amortizations (recognized in net periodic benefit cost):
Accumulated other comprehensive (income) loss at end of year, before tax	0	0
Discount rate used to measure the benefit obligations (as a percent)	3.25%	4.00%
Postretirement Plan
Change in benefit obligation
Benefit obligation at beginning of year	5,217,000	6,675,000
Interest cost	198,000	174,000	293,000
Actuarial (gain) loss	-63,000	-1,241,000	-721,000
Benefits paid	-368,000	-391,000
Projected benefit obligation at end of year	4,984,000	5,217,000	6,675,000
Change in fair value of plan assets:
Fair value of plan assets at beginning of year	0	0
Actual (loss) on plan assets	0	0
Benefits paid	-368,000	-391,000
TCF contributions	368,000	391,000
Fair value of plan assets at end of year	0	0	0
Funded status of plans, end of period	-4,984,000	-5,217,000
Amounts recognized in the Consolidated Statements of Financial Condition:
Prepaid (accrued) benefit cost at end of year	-4,984,000	-5,217,000
Prior service cost	-331,000	-378,000
Accumulated other comprehensive income, before tax	-331,000	-378,000	-424,000
Total recognized asset (liability)	-5,315,000	-5,595,000
Changes recognized in accumulated other comprehensive loss
Accumulated other comprehensive (income) loss at the beginning of the year, before tax	-378,000	-424,000	-301,000
Prior service cost	0	0	-151,000
Amortizations (recognized in net periodic benefit cost):
Prior service credit	47,000	46,000	28,000
Total recognized in other comprehensive income (loss)	47,000	46,000	-123,000
Accumulated other comprehensive (income) loss at end of year, before tax	($331,000)	($378,000)	($424,000)
Discount rate used to measure the benefit obligations (as a percent)	3.25%	4.00%

Employee_Benefit_Plans_Details2

Employee Benefit Plans (Details 3) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Pension Plan
Employee Benefit Plans
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate	4.00%	3.00%	4.00%
Fair value of plan assets	$44,678	$51,018	$53,617
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Return on Assets	1.50%	1.50%	1.50%
Pension Plan | Measurement of fair value on a recurring basis | Level 1 | U.S. Treasury bills
Employee Benefit Plans
Fair value of plan assets	0	47,999
Pension Plan | Measurement of fair value on a recurring basis | Level 1 | Fixed income mutual funds
Employee Benefit Plans
Fair value of plan assets	22,532	0
Pension Plan | Measurement of fair value on a recurring basis | Level 1 | Money market mutual funds
Employee Benefit Plans
Fair value of plan assets	16,088	3,019
Pension Plan | Measurement of fair value on a recurring basis | Level 1 | Cash
Employee Benefit Plans
Fair value of plan assets	71	0
Pension Plan | Measurement of fair value on a recurring basis | Level 2
Employee Benefit Plans
Fair value of plan assets	44,678	51,018
Pension Plan | Measurement of fair value on a recurring basis | Level 2 | Collective investment fund
Employee Benefit Plans
Fair value of plan assets	4,961	0
Pension Plan | Measurement of fair value on a recurring basis | Level 2 | Mortgage-backed securities
Employee Benefit Plans
Fair value of plan assets	1,026	0
Postretirement Plan
Employee Benefit Plans
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate	4.00%	2.75%	4.00%
Fair value of plan assets	$0	$0	$0

Employee_Benefit_Plans_Details3

Employee Benefit Plans (Details 4) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Pension Plan
Net periodic benefit cost included in compensation and employee benefits expense
Interest cost	$1,587	$1,292	$1,763
Loss on plan assets	511	336	277
Defined Benefit Plan, Actuarial Gain (Loss)	-1,862	2,196	-289
Net periodic benefit plan cost	3,960	-568	2,329
Postretirement Plan
Net periodic benefit cost included in compensation and employee benefits expense
Interest cost	198	174	293
Loss on plan assets	0	0
Defined Benefit Plan, Actuarial Gain (Loss)	63	1,241	721
Amortization of prior service cost	-47	-46	-28
Net periodic benefit plan cost	$88	($1,113)	($456)

Employee_Benefit_Plans_Details4

Employee Benefit Plans (Details 5) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Maximum
Employee Benefit Plans
Average estimated duration of Pension and Postretirement Plans	8 years
Minimum
Employee Benefit Plans
Average estimated duration of Pension and Postretirement Plans	7 years
Pension Plan
Employee Benefit Plans
Actual return (loss) on plan assets, net of administrative expenses (as a percent)	-1.00%	-0.60%
Expected actuarial return on plan assets	$700,000	$800,000
Weighted-average return of the indexes consistent with the Plan's current investment strategy, net of administrative expenses (as a percent)	3.20%
Change in net periodic benefit cost as a result of 1% difference in the expected return on plan assets	400,000
Discount rate (as a percent)	3.25%	4.00%
Decrease in net period benefit cost due to change in discount rate	-1,900,000
Increase in net periodic benefit cost due to changes in plan participant census	-32,000
Contributions to plan during the year	0	0
Pension Plan | Maximum
Employee Benefit Plans
Eligible contributions by employer	10,900,000
Postretirement Plan
Employee Benefit Plans
Prior service credits expected to be recognized as components of net periodic benefit cost	46,000
Discount rate (as a percent)	3.25%	4.00%
Decrease in net period benefit cost due to change in discount rate	300,000
Reduction in net periodic benefit cost due to change in actuarially estimated cost	600,000
Increase in net periodic benefit obligation due to updated mortality tables and demographic changes	300,000
Expected contribution	500,000
Contributions to plan during the year	$368,000	$391,000

Employee_Benefit_Plans_Details5

Employee Benefit Plans (Details 6) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Pension Plan
Expected future benefit payments used to determine projected benefit obligations
2015	$4,209
2016	3,549
2017	2,881
2018	3,036
2019	3,138
2020 - 2024	12,284
Postretirement Plan
Expected future benefit payments used to determine projected benefit obligations
2015	505
2016	486
2017	466
2018	445
2019	424
2020 - 2024	1,801
Assumed health care cost trend rates for the Postretirement Plan
Health care cost trend rate assumed for next year (as a percent)	5.80%	6.00%
Final health care cost trend rate (as a percent)	5.00%	5.00%
1% change in assumed health care cost trend rates
Effect on total service and interest cost components, increase	9
Effect on total service and interest cost components, decrease	-9
Effect on postretirement benefits obligations, increase	217
Effect on postretirement benefits obligations, decrease	($196)

Financial_Instruments_with_Off2

Financial Instruments with Off-Balance Sheet Risk (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Financial instruments with off-balance sheet risk
Commitments to extend credit	$2,064,705	$1,915,104
Standby letters of credit and guarantees on industrial revenue bonds	14,676	13,364
Total financial instruments with off-balance-sheet risk	2,079,381	1,928,468
Consumer Real Estate and Other Receivable [Member]
Financial instruments with off-balance sheet risk
Commitments to extend credit	1,314,826	1,274,006
Commercial
Financial instruments with off-balance sheet risk
Commitments to extend credit	609,618	482,777
Leasing and equipment finance, other
Financial instruments with off-balance sheet risk
Commitments to extend credit	$140,261	$158,321

Derivative_Instruments_Details

Derivative Instruments (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014
Net Investment Hedges
Fair value of foreign exchange contracts
Period for settling forward foreign exchange contracts	30 days
Interest Rate Swap | Not Designated as Hedges
Fair value of foreign exchange contracts
Period for settling forward foreign exchange contracts	30 days
Interest Rate Swap | Not Designated as Hedges | Minimum
Fair value of foreign exchange contracts
Period of contracts having fixed maturity dates	3 years
Interest Rate Swap | Not Designated as Hedges | Maximum
Fair value of foreign exchange contracts
Period of contracts having fixed maturity dates	10 years
Swap agreement
Fair value of foreign exchange contracts
Amount of cash collateral posted	5.1
Forward foreign exchange contracts
Fair value of foreign exchange contracts
Amount of cash collateral posted	1.2

Derivative_Instruments_Details1

Derivative Instruments (Details 2) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Derivative assets
Gross Amounts Recognized	$5,294	$282
Gross Amounts Offset	-1,179	-151
Net Amount Presented	4,115	131
Derivative liabilities
Gross Amounts Recognized	2,675	1,952
Gross Amounts Offset	-2,527	-1,031
Net Amount Presented	148	921
Forward foreign exchange contracts | Designated as Hedges
Derivative assets
Notional Amount	42,165
Gross Amounts Recognized	509
Gross Amounts Offset	0
Net Amount Presented	509
Derivative liabilities
Notional Amount		32,761
Gross Amounts Recognized		87
Gross Amounts Offset		0
Net Amount Presented		87
Forward foreign exchange contracts | Not Designated as Hedges
Derivative assets
Notional Amount	275,962	98,847
Gross Amounts Recognized	2,702	151
Gross Amounts Offset	-1,179	-151
Net Amount Presented	1,523	0
Derivative liabilities
Notional Amount	189,310	363,475
Gross Amounts Recognized	177	834
Gross Amounts Offset	-29	0
Net Amount Presented	148	834
Swap agreements
Derivative assets
Notional Amount	101,166	13,500
Gross Amounts Recognized	1,798	131
Gross Amounts Offset	0	0
Net Amount Presented	1,798	131
Derivative liabilities
Notional Amount	114,970	41,358
Gross Amounts Recognized	2,498	1,031
Gross Amounts Offset	-2,498	-1,031
Net Amount Presented	0	0
Interest Rate Lock Commitments
Amounts relevant to offsetting of derivative assets and liabilities
Derivative, Higher Remaining Maturity Range	60 days
Derivative assets
Notional Amount	15,124
Gross Amounts Recognized	285
Gross Amounts Offset	0
Net Amount Presented	$285

Derivative_Instruments_Details2

Derivative Instruments (Details 3) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Derivatives instruments, gain (loss)
Derivative, Gain (Loss) on Derivative, Net	$38,958,000	$25,170,000	($7,530,000)
Other comprehensive income (loss):
Net investment hedges	3,126,000	1,625,000	-630,000
Net unrealized gain (loss)	3,126,000	1,625,000	-630,000
Credit risk-related contingent features
Forward foreign exchange contracts with credit risk-related contingent features, notional value	124,800,000
Additional collateral required, if TCF was rated less than BB- by Standard and Poor's	2,500,000
Forward foreign exchange contracts with credit risk-related contingent features, net liability amount	0
Cash Flow Hedges
Derivatives instruments, gain (loss)
Derivative, Gain (Loss) on Derivative, Net	0	0	-6,000
NetRealizedGain(Loss)OnDerivativeInstrumentsRecognizedInNonInterestIncome [Member] | Not Designated as Hedges
Derivatives instruments, gain (loss)
Derivative, Gain (Loss) on Derivative, Net	-79,000	0	0
NetRealizedGain(Loss)OnDerivativeInstrumentsRecognizedInNonInterestExpense [Member] | Not Designated as Hedges
Derivatives instruments, gain (loss)
Derivative, Gain (Loss) on Derivative, Net	38,752,000	25,170,000	-7,524,000
Interest Rate Lock Commitments | NetRealizedGain(Loss)OnDerivativeInstrumentsRecognizedInNonInterestIncome [Member]
Derivatives instruments, gain (loss)
Derivative, Gain (Loss) on Derivative, Net	$285,000	$0	$0

Fair_Values_Disclosures_Detail

Fair Values Disclosures (Details) (Measurement of fair value on a non-recurring basis, USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Measurement of fair value on a non-recurring basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Asset Impairment Charges	$14.80	$15.60

Fair_Values_Disclosures_Detail1

Fair Values Disclosures (Details 1) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Assets and liabilities measured at fair value on a non-recurring basis
Real estate owned	$65,700	$68,900
Interest-only strips	48,600	64,900
Held-to-maturity Securities	214,454	19,912
U.S. Government sponsored enterprises and federal agencies
Assets and liabilities measured at fair value on a non-recurring basis
Held-to-maturity Securities	209,538	14,610
Other securities
Assets and liabilities measured at fair value on a non-recurring basis
Held-to-maturity Securities	4,916	5,302	5,700
Measurement of fair value on a recurring basis
Assets and liabilities measured at fair value on a non-recurring basis
Fair value carrying amount	490,618	568,070
Liabilities	21,420	18,676
Measurement of fair value on a recurring basis | Loans and Leases Held for Sale
Assets and liabilities measured at fair value on a non-recurring basis
Fair value carrying amount	3,308
Measurement of fair value on a recurring basis | Foreign Exchange Forward
Assets and liabilities measured at fair value on a non-recurring basis
Fair value carrying amount	3,211	151
Liabilities	177	921
Measurement of fair value on a recurring basis | Swap agreements
Assets and liabilities measured at fair value on a non-recurring basis
Fair value carrying amount	1,798	131
Liabilities	2,498	1,031
Measurement of fair value on a recurring basis | Interest Rate Lock Commitments
Assets and liabilities measured at fair value on a non-recurring basis
Fair value carrying amount	285
Measurement of fair value on a recurring basis | Forward Loan Sales Commitments
Assets and liabilities measured at fair value on a non-recurring basis
Fair value carrying amount	19
Liabilities	42
Measurement of fair value on a recurring basis | Assets Held-in-trust for deferred compensation plans
Assets and liabilities measured at fair value on a non-recurring basis
Fair value carrying amount	18,703	16,724
Measurement of fair value on a recurring basis | Liabilities held in trust for deferred compensation plans
Assets and liabilities measured at fair value on a non-recurring basis
Liabilities	18,703	16,724
Measurement of fair value on a recurring basis | U.S. Government sponsored enterprises and federal agencies
Assets and liabilities measured at fair value on a non-recurring basis
Fair value carrying amount	463,239	548,037
Measurement of fair value on a recurring basis | Mortgage-backed securities, Other
Assets and liabilities measured at fair value on a non-recurring basis
Fair value carrying amount	55	93
Measurement of fair value on a recurring basis | Other securities
Assets and liabilities measured at fair value on a non-recurring basis
Fair value carrying amount		2,934
Measurement of fair value on a non-recurring basis
Assets and liabilities measured at fair value on a non-recurring basis
Loans	164,897	214,183
Repossessed and returned assets	2,988	2,267
Interest-only strips	41,204	33,098
Fair value carrying amount	264,812	305,893
Held-to-maturity Securities	1,516	1,902
Measurement of fair value on a non-recurring basis | Consumer real estate
Assets and liabilities measured at fair value on a non-recurring basis
Real estate owned	40,502	40,355
Measurement of fair value on a non-recurring basis | Commercial real estate
Assets and liabilities measured at fair value on a non-recurring basis
Real estate owned	13,705	14,088
Level 1
Assets and liabilities measured at fair value on a non-recurring basis
Loans	0	0
Interest-only strips	0	0
Held-to-maturity Securities	0	0
Level 1 | Measurement of fair value on a recurring basis
Assets and liabilities measured at fair value on a non-recurring basis
Fair value carrying amount	18,703	19,658
Liabilities	18,703	16,724
Level 1 | Measurement of fair value on a recurring basis | Loans and Leases Held for Sale
Assets and liabilities measured at fair value on a non-recurring basis
Fair value carrying amount	0
Level 1 | Measurement of fair value on a recurring basis | Foreign Exchange Forward
Assets and liabilities measured at fair value on a non-recurring basis
Fair value carrying amount	0	0
Liabilities	0	0
Level 1 | Measurement of fair value on a recurring basis | Swap agreements
Assets and liabilities measured at fair value on a non-recurring basis
Fair value carrying amount	0	0
Liabilities	0	0
Level 1 | Measurement of fair value on a recurring basis | Interest Rate Lock Commitments
Assets and liabilities measured at fair value on a non-recurring basis
Fair value carrying amount	0
Level 1 | Measurement of fair value on a recurring basis | Forward Loan Sales Commitments
Assets and liabilities measured at fair value on a non-recurring basis
Fair value carrying amount	0
Liabilities	0
Level 1 | Measurement of fair value on a recurring basis | Assets Held-in-trust for deferred compensation plans
Assets and liabilities measured at fair value on a non-recurring basis
Fair value carrying amount	18,703	16,724
Level 1 | Measurement of fair value on a recurring basis | Liabilities held in trust for deferred compensation plans
Assets and liabilities measured at fair value on a non-recurring basis
Liabilities	18,703	16,724
Level 1 | Measurement of fair value on a recurring basis | U.S. Government sponsored enterprises and federal agencies
Assets and liabilities measured at fair value on a non-recurring basis
Fair value carrying amount	0	0
Level 1 | Measurement of fair value on a recurring basis | Mortgage-backed securities, Other
Assets and liabilities measured at fair value on a non-recurring basis
Fair value carrying amount	0	0
Level 1 | Measurement of fair value on a recurring basis | Other securities
Assets and liabilities measured at fair value on a non-recurring basis
Fair value carrying amount		2,934
Level 1 | Measurement of fair value on a non-recurring basis
Assets and liabilities measured at fair value on a non-recurring basis
Loans	0	0
Repossessed and returned assets	0	0
Interest-only strips	0	0
Fair value carrying amount	0	0
Held-to-maturity Securities	0	0
Level 1 | Measurement of fair value on a non-recurring basis | Consumer real estate
Assets and liabilities measured at fair value on a non-recurring basis
Real estate owned	0	0
Level 1 | Measurement of fair value on a non-recurring basis | Commercial real estate
Assets and liabilities measured at fair value on a non-recurring basis
Real estate owned	0	0
Level 2
Assets and liabilities measured at fair value on a non-recurring basis
Loans	0	0
Interest-only strips	0	0
Held-to-maturity Securities	217,418	14,610
Level 2 | Measurement of fair value on a recurring basis
Assets and liabilities measured at fair value on a non-recurring basis
Fair value carrying amount	468,248	548,319
Liabilities	2,054	1,053
Level 2 | Measurement of fair value on a recurring basis | Loans and Leases Held for Sale
Assets and liabilities measured at fair value on a non-recurring basis
Fair value carrying amount	0
Level 2 | Measurement of fair value on a recurring basis | Foreign Exchange Forward
Assets and liabilities measured at fair value on a non-recurring basis
Fair value carrying amount	3,211	151
Liabilities	177	921
Level 2 | Measurement of fair value on a recurring basis | Swap agreements
Assets and liabilities measured at fair value on a non-recurring basis
Fair value carrying amount	1,798	131
Liabilities	1,877	132
Level 2 | Measurement of fair value on a recurring basis | Interest Rate Lock Commitments
Assets and liabilities measured at fair value on a non-recurring basis
Fair value carrying amount	0
Level 2 | Measurement of fair value on a recurring basis | Forward Loan Sales Commitments
Assets and liabilities measured at fair value on a non-recurring basis
Fair value carrying amount	0
Liabilities	0
Level 2 | Measurement of fair value on a recurring basis | Assets Held-in-trust for deferred compensation plans
Assets and liabilities measured at fair value on a non-recurring basis
Fair value carrying amount	0	0
Level 2 | Measurement of fair value on a recurring basis | Liabilities held in trust for deferred compensation plans
Assets and liabilities measured at fair value on a non-recurring basis
Liabilities	0	0
Level 2 | Measurement of fair value on a recurring basis | U.S. Government sponsored enterprises and federal agencies
Assets and liabilities measured at fair value on a non-recurring basis
Fair value carrying amount	463,239	548,037
Level 2 | Measurement of fair value on a recurring basis | Mortgage-backed securities, Other
Assets and liabilities measured at fair value on a non-recurring basis
Fair value carrying amount	0	0
Level 2 | Measurement of fair value on a recurring basis | Other securities
Assets and liabilities measured at fair value on a non-recurring basis
Fair value carrying amount		0
Level 2 | Measurement of fair value on a non-recurring basis
Assets and liabilities measured at fair value on a non-recurring basis
Loans	0	0
Repossessed and returned assets	1,563	1,537
Interest-only strips	0	0
Fair value carrying amount	6,402	1,537
Held-to-maturity Securities	0	0
Level 2 | Measurement of fair value on a non-recurring basis | Consumer real estate
Assets and liabilities measured at fair value on a non-recurring basis
Real estate owned	0	0
Level 2 | Measurement of fair value on a non-recurring basis | Commercial real estate
Assets and liabilities measured at fair value on a non-recurring basis
Real estate owned	4,839	0
Level 3
Assets and liabilities measured at fair value on a non-recurring basis
Loans	18,724	25,216
Interest-only strips	73,058	85,265
Held-to-maturity Securities	4,916	5,302
Level 3 | Measurement of fair value on a recurring basis
Assets and liabilities measured at fair value on a non-recurring basis
Fair value carrying amount	3,667	93
Liabilities	663	899
Level 3 | Measurement of fair value on a recurring basis | Loans and Leases Held for Sale
Assets and liabilities measured at fair value on a non-recurring basis
Fair value carrying amount	3,308
Level 3 | Measurement of fair value on a recurring basis | Foreign Exchange Forward
Assets and liabilities measured at fair value on a non-recurring basis
Fair value carrying amount	0	0
Liabilities	0	0
Level 3 | Measurement of fair value on a recurring basis | Swap agreements
Assets and liabilities measured at fair value on a non-recurring basis
Fair value carrying amount	0	0
Liabilities	621	899
Level 3 | Measurement of fair value on a recurring basis | Interest Rate Lock Commitments
Assets and liabilities measured at fair value on a non-recurring basis
Fair value carrying amount	285
Level 3 | Measurement of fair value on a recurring basis | Forward Loan Sales Commitments
Assets and liabilities measured at fair value on a non-recurring basis
Fair value carrying amount	19
Liabilities	42
Level 3 | Measurement of fair value on a recurring basis | Assets Held-in-trust for deferred compensation plans
Assets and liabilities measured at fair value on a non-recurring basis
Fair value carrying amount	0	0
Level 3 | Measurement of fair value on a recurring basis | Liabilities held in trust for deferred compensation plans
Assets and liabilities measured at fair value on a non-recurring basis
Liabilities	0	0
Level 3 | Measurement of fair value on a recurring basis | U.S. Government sponsored enterprises and federal agencies
Assets and liabilities measured at fair value on a non-recurring basis
Fair value carrying amount	0	0
Level 3 | Measurement of fair value on a recurring basis | Mortgage-backed securities, Other
Assets and liabilities measured at fair value on a non-recurring basis
Fair value carrying amount	55	93
Level 3 | Measurement of fair value on a recurring basis | Other securities
Assets and liabilities measured at fair value on a non-recurring basis
Fair value carrying amount		0
Level 3 | Measurement of fair value on a non-recurring basis
Assets and liabilities measured at fair value on a non-recurring basis
Loans	164,897	214,183
Repossessed and returned assets	1,425	730
Interest-only strips	41,204	33,098
Fair value carrying amount	258,410	304,356
Held-to-maturity Securities	1,516	1,902
Level 3 | Measurement of fair value on a non-recurring basis | Consumer real estate
Assets and liabilities measured at fair value on a non-recurring basis
Real estate owned	40,502	40,355
Level 3 | Measurement of fair value on a non-recurring basis | Commercial real estate
Assets and liabilities measured at fair value on a non-recurring basis
Real estate owned	$8,866	$14,088

Fair_Values_Disclosures_Detail2

Fair Values Disclosures (Details 2) (Level 3, Measurement of fair value on a recurring basis, USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Transfers out of Level 3	$0	$0
Interest Rate Lock Commitments
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Beginning balance	0	0	0
Transfers out of Level 3			0
Net income (loss)	285		0
Other comprehensive loss			0
Sales	0
Purchases / originations	0		0
Principal paydowns / settlements	0	0	0
Ending balance	285	0	0
Forward Loan Sales Commitments
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Beginning balance	0	0	0
Transfers out of Level 3			0
Net income (loss)	-23		0
Other comprehensive loss			0
Sales	0
Purchases / originations	0		0
Principal paydowns / settlements	0	0	0
Ending balance	-23	0	0
Swap agreements
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Beginning balance	-899	-1,227	0
Transfers out of Level 3			0
Net income (loss)	-47		-150
Other comprehensive loss			0
Sales	0
Purchases / originations	0		-1,434
Principal paydowns / settlements	325	328	357
Ending balance	-621	-899	-1,227
Available-for-sale Securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	93	127	1,450
Transfers out of Level 3			-1,098
Net income (loss)	0		0
Other comprehensive loss			-100
Sales	0
Purchases / originations	0		0
Principal paydowns / settlements	-38	-34	-125
Ending balance	55	93	127
Loans and Leases Held for Sale
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	0	0	0
Transfers out of Level 3			0
Net income (loss)	72		0
Other comprehensive loss			0
Sales	-39,246
Purchases / originations	42,482		0
Principal paydowns / settlements	0	0	0
Ending balance	$3,308	$0	$0

Fair_Values_Disclosures_Detail3

Fair Values Disclosures (Details 3) (Loans and Leases Held for Sale, USD $)	12 Months Ended
	Dec. 31, 2014
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair value carrying amount	$3,308,000
Aggregate unpaid principal amount	3,205,000
Fair value carrying amount less aggregate unpaid principal	103,000
Gain (Loss) on Sales of Consumer Loans
Fair Value, Option, Quantitative Disclosures [Line Items]
Net gain from initial measurement of the above loans and subsequent changes in fair value for loans outstanding	$900,000

Fair_Values_Disclosures_Detail4

Fair Values Disclosures (Details 4) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Financial instrument assets:
Securities held to maturity	$214,454	$19,912
Loans:
Commercial real estate	2,624,255	2,743,697
Allowance for loan losses	-164,169	-252,230	-267,128
Interest-only strips	48,600	64,900
Financial instruments with off-balance sheet risk:
Commitments to extend credit	2,064,705	1,915,104
Standby letters of credit	14,676	13,364
Total financial instruments with off-balance-sheet risk	2,079,381	1,928,468
Level 1
Financial instrument assets:
Investments	0	0
Securities held to maturity	0	0
Loans and leases held for sale	0	0
Loans:
Consumer real estate	0	0
Commercial real estate	0	0
Commercial business	0	0
Equipment finance	0	0
Inventory finance	0	0
Auto finance	0	0
Other	0	0
Allowance for loan losses	0	0
Interest-only strips	0	0
Total financial instrument assets	0	0
Financial instrument liabilities:
Deposits	12,400,693	12,006,364
Long-term borrowings	0	0
Total financial instrument liabilities	12,400,693	12,006,364
Financial instruments with off-balance sheet risk:
Commitments to extend credit	0	0
Standby letters of credit	0	0
Total financial instruments with off-balance-sheet risk	0	0
Level 2
Financial instrument assets:
Investments	85,492	94,326
Securities held to maturity	217,418	14,610
Loans and leases held for sale	0	0
Loans:
Consumer real estate	0	0
Commercial real estate	0	0
Commercial business	0	0
Equipment finance	0	0
Inventory finance	0	0
Auto finance	0	0
Other	0	0
Allowance for loan losses	0	0
Interest-only strips	0	0
Total financial instrument assets	302,910	108,936
Financial instrument liabilities:
Deposits	3,063,850	2,434,946
Long-term borrowings	1,246,221	1,496,017
Total financial instrument liabilities	4,310,071	3,930,963
Financial instruments with off-balance sheet risk:
Commitments to extend credit	25,885	29,057
Standby letters of credit	-47	-52
Total financial instruments with off-balance-sheet risk	25,838	29,005
Level 3
Financial instrument assets:
Investments	0	0
Securities held to maturity	4,916	5,302
Loans and leases held for sale	139,370	84,341
Loans:
Consumer real estate	5,836,770	6,279,328
Commercial real estate	2,575,625	2,673,825
Commercial business	512,083	392,947
Equipment finance	1,787,271	1,534,905
Inventory finance	1,864,786	1,653,345
Auto finance	1,927,384	1,256,357
Other	18,724	25,216
Allowance for loan losses	0	0
Interest-only strips	73,058	85,265
Total financial instrument assets	14,739,987	13,990,831
Financial instrument liabilities:
Deposits	0	0
Long-term borrowings	8,054	10,838
Total financial instrument liabilities	8,054	10,838
Financial instruments with off-balance sheet risk:
Commitments to extend credit	0	0
Standby letters of credit	0	0
Total financial instruments with off-balance-sheet risk	0	0
Carrying Amount
Financial instrument assets:
Investments	85,492	94,326
Securities held to maturity	214,454	19,912
Loans and leases held for sale	132,266	79,768
Loans:
Consumer real estate	5,682,364	6,339,326
Commercial real estate	2,624,255	2,743,697
Commercial business	533,410	404,655
Equipment finance	1,806,808	1,546,134
Inventory finance	1,877,090	1,664,377
Auto finance	1,915,061	1,239,386
Other	24,144	26,743
Allowance for loan losses	-164,169	-252,230
Interest-only strips	69,789	84,561
Total financial instrument assets	14,800,964	13,990,655
Financial instrument liabilities:
Deposits	15,449,882	14,432,776
Long-term borrowings	1,232,065	1,483,325
Total financial instrument liabilities	16,681,947	15,916,101
Financial instruments with off-balance sheet risk:
Commitments to extend credit	25,885	29,057
Standby letters of credit	-47	-52
Total financial instruments with off-balance-sheet risk	25,838	29,005
Estimated Fair Value
Financial instrument assets:
Investments	85,492	94,326
Securities held to maturity	222,334	19,912
Loans and leases held for sale	139,370	84,341
Loans:
Consumer real estate	5,836,770	6,279,328
Commercial real estate	2,575,625	2,673,825
Commercial business	512,083	392,947
Equipment finance	1,787,271	1,534,905
Inventory finance	1,864,786	1,653,345
Auto finance	1,927,384	1,256,357
Other	18,724	25,216
Allowance for loan losses	0	0
Interest-only strips	73,058	85,265
Total financial instrument assets	15,042,897	14,099,767
Financial instrument liabilities:
Deposits	15,464,543	14,441,310
Long-term borrowings	1,254,275	1,506,855
Total financial instrument liabilities	16,718,818	15,948,165
Financial instruments with off-balance sheet risk:
Commitments to extend credit	25,885	29,057
Standby letters of credit	-47	-52
Total financial instruments with off-balance-sheet risk	$25,838	$29,005

Earnings_Per_Common_Share_Deta

Earnings Per Common Share (Details) (USD $)	12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Basic Earnings Per Common Share
Net income (loss) attributable to TCF Financial Corporation	$174,187	$151,668	($212,884)
Preferred stock dividends	-19,388	-19,065	-5,606
Net income (loss) available to common stockholders	154,799	132,603	-218,490
Earnings allocated to participating securities	40	71	50
Earnings allocated to common stock	154,759	132,532	-218,540
Weighted-average shares outstanding	166,542,848	164,229,421	162,288,902
Restricted stock (in shares)	-2,961,413	-3,213,417	-3,020,094
Weighted-average common shares outstanding for basic earnings per common share	163,581,435	161,016,004	159,268,808
Basic earnings per common share (in dollars per share)	$0.95	$0.82	($1.37)
Diluted Earnings Per Common Share
Earnings (loss) allocated to common stock	$154,759	$132,532	($218,540)
Weighted-average common shares outstanding used in basic earnings per common share calculation	163,581,435	161,016,004	159,268,808
Net dilutive effect of:
Non-participating restricted stock (in shares)	250,499	719,459	0
Stock options (in shares)	252,892	191,092	0
Weighted-average common shares outstanding for diluted earnings per common share	164,084,826	161,926,555	159,268,808
Diluted earnings per common share (in dollars per share)	$0.94	$0.82	($1.37)

Earnings_Per_Common_Share_Deta1

Earnings Per Common Share (Details 2) (Non-participating restricted stock, stock options and warrants)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Non-participating restricted stock, stock options and warrants
Antidilutive Securities Excluded from Computation of Earnings Per Share
Anti-dilutive shares	4.2	3.8	5.1

Other_Expense_Details

Other Expense (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Other Income and Expenses [Abstract]
Loan and lease processing	$20,294	$13,787	$9,567
Professional fees	18,949	18,642	13,608
Card processing and issuance cost	16,588	15,868	15,586
Outside processing	13,288	13,767	12,919
Telecommunications	11,911	11,720	11,735
Travel	11,481	12,810	11,740
Other	87,393	81,183	88,742
Other Noninterest Expense	$179,904	$167,777	$163,897

Business_Segments_Details

Business Segments (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Revenue (expense) from operations:
Net interest income (expense)	$815,629	$802,624	$780,019
Provision for credit losses	95,737	118,368	247,443
Non-interest income	433,267	404,058	490,423
Non-interest expense	871,777	845,269	1,362,554
Income tax expense (benefit)	99,766	84,345	-132,858
Income after income tax expense	181,616	158,700	-206,697
Income attributable to non-controlling interest	7,429	7,032	6,187
Preferred stock dividends	19,388	19,065	5,606
Net income (loss) available to common stockholders	154,799	132,603	-218,490
Total assets	19,394,611	18,379,840	18,225,917
Revenues from external customers:
Interest income	874,229	864,540	884,623
Non-interest income	433,267	404,058	490,423
Total	1,307,496	1,268,598	1,375,046
Operating | Lending
Revenue (expense) from operations:
Net interest income (expense)	592,409	568,286	524,358
Provision for credit losses	92,800	115,408	245,355
Non-interest income	211,166	168,387	138,514
Non-interest expense	426,290	401,326	367,172
Income tax expense (benefit)	102,398	76,663	13,272
Income after income tax expense	182,087	143,276	37,073
Income attributable to non-controlling interest	7,429	7,032	6,187
Preferred stock dividends	0	0	0
Net income (loss) available to common stockholders	174,658	136,244	30,886
Total assets	16,871,154	16,197,449	15,694,693
Revenues from external customers:
Interest income	852,019	840,250	842,718
Non-interest income	211,166	168,387	138,514
Total	1,063,185	1,008,637	981,232
Operating | Funding
Revenue (expense) from operations:
Net interest income (expense)	226,327	237,289	258,283
Provision for credit losses	2,937	2,960	2,088
Non-interest income	220,568	235,238	338,895
Non-interest expense	434,141	442,557	969,805
Income tax expense (benefit)	3,722	9,750	-135,432
Income after income tax expense	6,095	17,260	-239,283
Income attributable to non-controlling interest	0	0	0
Preferred stock dividends	0	0	0
Net income (loss) available to common stockholders	6,095	17,260	-239,283
Total assets	6,488,853	7,862,779	7,249,958
Revenues from external customers:
Interest income	22,210	24,290	41,905
Non-interest income	220,506	235,185	338,848
Total	242,716	259,475	380,753
Operating | Support Services
Revenue (expense) from operations:
Net interest income (expense)	166	3	41
Provision for credit losses	0	0	0
Non-interest income	140,779	136,584	140,784
Non-interest expense	147,549	139,864	152,677
Income tax expense (benefit)	-1,932	8	-7,790
Income after income tax expense	-4,672	-3,285	-4,062
Income attributable to non-controlling interest	0	0	0
Preferred stock dividends	19,388	19,065	5,606
Net income (loss) available to common stockholders	-24,060	-22,350	-9,668
Total assets	239,425	228,863	148,513
Revenues from external customers:
Interest income	0	0	0
Non-interest income	1,595	486	13,061
Total	1,595	486	13,061
Eliminations
Revenue (expense) from operations:
Net interest income (expense)	-3,273	-2,954	-2,663
Provision for credit losses	0	0	0
Non-interest income	-139,246	-136,151	-127,770
Non-interest expense	-136,203	-138,478	-127,100
Income tax expense (benefit)	-4,422	-2,076	-2,908
Income after income tax expense	-1,894	1,449	-425
Income attributable to non-controlling interest	0	0	0
Preferred stock dividends	0	0	0
Net income (loss) available to common stockholders	-1,894	1,449	-425
Total assets	-4,204,821	-5,909,251	-4,867,247
Revenues from external customers:
Interest income	0	0	0
Non-interest income	0	0	0
Total	$0	$0	$0

Parent_Company_Financial_Infor2

Parent Company Financial Information (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
In Thousands, unless otherwise specified
Assets
Other assets	$484,377	$461,743
Total assets	19,394,611	18,379,840	18,225,917
Other liabilities	572,875	494,062
Total liabilities	17,259,247	16,415,081
Equity	2,121,649	1,952,968
Total liabilities and equity	19,394,611	18,379,840
TCF Financial Corporation
Assets
Cash and cash equivalents	71,781	62,775	85,337	133,120
Investment in bank subsidiary	2,037,781	1,863,563
Accounts receivable from bank subsidiary	13,862	21,706
Other assets	12,628	19,498
Total assets	2,136,052	1,967,542
Other liabilities	14,403	14,574
Total liabilities	14,403	14,574
Equity	2,121,649	1,952,968
Total liabilities and equity	$2,136,052	$1,967,542

Parent_Company_Financial_Infor3

Parent Company Financial Information (Details 1) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Condensed Statements of (Loss) Income
Interest expense	$58,600	$61,916	$104,604
Net interest income	815,629	802,624	780,019
Other	10,704	6,196	5,974
Compensation and employee benefits	452,942	429,188	393,841
Occupancy and equipment	139,023	134,694	130,792
Other	179,904	167,777	163,897
Total non-interest expense	871,777	845,269	1,362,554
Income (loss) before income tax expense (benefit)	281,382	243,045	-339,555
Income tax benefit	-99,766	-84,345	132,858
Net Income (Loss)	174,187	151,668	-212,884
Preferred stock dividends	19,388	19,065	5,606
Net income (loss) available to common stockholders	154,799	132,603	-218,490
TCF Financial Corporation
Condensed Statements of (Loss) Income
Interest income	365	419	355
Interest expense	0	0	7,952
Net interest income	365	419	-7,597
Dividends from TCF Bank	19,000	0	18,000
Affiliate service fees	22,461	23,338	17,089
Other	1,178	407	12,936
Total non-interest income	42,639	23,745	48,025
Compensation and employee benefits	21,193	22,108	14,703
Occupancy and equipment	338	322	298
Other	3,436	3,352	15,731
Total non-interest expense	24,967	25,782	30,732
Income (loss) before income tax expense (benefit)	18,037	-1,618	9,696
Income tax benefit	52	309	2,766
Income (loss) before equity in undistributed earnings of subsidiaries	18,089	-1,309	12,462
Equity (deficit) in undistributed earnings of bank subsidiary	156,098	152,977	-225,346
Net Income (Loss)	174,187	151,668	-212,884
Preferred stock dividends	19,388	19,065	5,606
Net income (loss) available to common stockholders	$154,799	$132,603	($218,490)

Parent_Company_Financial_Infor4

Parent Company Financial Information (Details 2) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Cash flows from operating activities:
Net Income (Loss)	$174,187	$151,668	($212,884)
Adjustments to reconcile net income to net cash provided by operating activities:
Other, net	-32,571	-36,288	14,839
Net cash provided by (used in) operating activities	311,750	411,034	496,663
Cash flows from investing activities:
Proceeds from sales of securities available for sale	2,813	46,506	2,089,044
Purchases of premises and equipment	-45,469	-37,859	-44,082
Other, net	30,140	35,636	39,949
Net cash provided by (used in) investing activities	-824,923	-481,789	123,519
Cash flows from financing activities:
Net proceeds from public offerings of preferred stock	0	0	263,240
Dividends paid on preferred stock	-19,388	-19,065	-5,606
Dividends paid on common stock	-32,731	-32,227	-31,904
Redemption of trust preferred securities	0	0	-115,010
Shares sold to TCF employee benefit plans	23,083	20,179	19,462
Stock compensation tax (expense) benefit	1,316	-473	-659
Exercise of stock options	740	0	0
Net cash provided by (used in) financing activities	713,347	-114,516	-909,539
TCF Financial Corporation
Cash flows from operating activities:
Net Income (Loss)	174,187	151,668	-212,884
Adjustments to reconcile net income to net cash provided by operating activities:
(Equity) deficit in undistributed earnings of bank subsidiary	-156,098	-152,977	225,346
(Gains) on sales of assets, net	-1,177	-350	-13,116
Other, net	16,430	9,962	9,561
Net cash provided by (used in) operating activities	33,342	8,303	8,907
Cash flows from investing activities:
Capital contributions to bank subsidiary	0	0	-192,000
Proceeds from sales of securities available for sale	2,813	0	0
Proceeds from sales of other securities	0	0	14,550
Purchases of premises and equipment	-260	-148	-6
Proceeds from sales of premises and equipment	91	0	0
Other, net	0	869	0
Net cash provided by (used in) investing activities	2,644	721	-177,456
Cash flows from financing activities:
Net proceeds from public offerings of preferred stock	0	0	263,240
Dividends paid on preferred stock	-19,388	-19,065	-5,606
Dividends paid on common stock	-32,731	-32,227	-31,904
Redemption of trust preferred securities	0	0	-115,010
Interest paid on trust preferred securities	0	0	-8,757
Shares sold to TCF employee benefit plans	23,083	20,179	19,462
Stock compensation tax (expense) benefit	1,316	-473	-659
Exercise of stock options	740	0	0
Net cash provided by (used in) financing activities	-26,980	-31,586	120,766
Net change in cash and due from banks	9,006	-22,562	-47,783
Cash and due from banks at beginning of period	62,775	85,337	133,120
Cash and due from banks at end of period	$71,781	$62,775	$85,337

Parent_Company_Financial_Infor5

Parent Company Financial Information (Details 3) (USD $)	Dec. 31, 2014
In Millions, unless otherwise specified
Condensed Financial Information of Parent Company Only Disclosure [Abstract]
Net profits for the current year combined with retained net profits for preceding two calendar years	$83.70

Accumulated_Other_Comprehensiv2

Accumulated Other Comprehensive Income (Loss) (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Securities available for sale, Before Tax
Unrealized gains (losses) arising during the period, Before Tax	$29,071	($61,177)	$19,794
Reclassification of net (gains) losses to net income, Before Tax	-76	-860	-89,879
Net unrealized gains (losses), Before Tax	28,995	-62,037	-70,085
Securities available for sale, Tax Effect
Unrealized gains (losses) arising during the period, Tax Effect	-10,932	23,053	-7,252
Reclassification of net gains (losses) to net income, Tax Effect	29	324	32,745
Net unrealized gains (losses), Tax Effect	-10,903	23,377	25,493
Securities available for sale, Net of Tax
Unrealized gains (losses) arising during the period, Net of Tax	18,139	-38,124	12,542
Reclassification of net (gains) losses to net income, Net of Tax	-47	-536	-57,134
Net unrealized gains (losses), Net of Tax	18,092	-38,660	-44,592
Foreign currency hedge, Net of Tax
Unrealized gains (losses) arising during the period	3,126	1,625	-630
Unrealized gains (losses) arising during the period, Tax Effect	-1,181	-614	239
Unrealized gains (losses) arising during the period, Net of Tax	1,945	1,011	-391
Foreign currency translation adjustment, Net of Tax
Unrealized gains (losses) arising during the period, Before Tax	-3,704	-1,979	531
Unrealized gains (losses) arising during the period, Tax Effect	0	0	0
Unrealized gains (losses) arising during the period, Net of Tax	-3,704	-1,979	531
Recognized postretirement prior service cost and translation obligation, Before Tax
Unrealized gains (losses) arising during the period, Before Tax	0	0	151
Reclassification of net (gains) losses to net income (loss), Tax Effect	-47	-46	-28
Recognized postretirement prior service cost and translation obligation, Tax Effect
Unrealized gains (losses) arising during the period, Tax Effect			-66
Reclassification of net (gains) losses to net income, Tax Effect	17	18	12
Recognized postretirement prior service cost and translation obligation, Net of Tax
Unrealized gains (losses) arising during the period, Net of Tax			85
Reclassification of net (gains) losses to net income, Net of Tax	-30	-28	-16
Total other comprehensive loss, Net of Tax
Total other comprehensive income (loss), Before Tax	28,370	-62,437	-70,061
Total other comprehensive income (loss), Tax Effect	-12,067	22,781	25,678
Total other comprehensive income (loss)	$16,303	($39,656)	($44,383)

Accumulated_Other_Comprehensiv3

Accumulated Other Comprehensive Income (Loss) (Details 2) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Changes in accumulated other comprehensive income by component
Comprehensive income at the beginning of the period	($27,213)	$12,443	$56,826
Other comprehensive income (loss)	16,380	-39,092	12,767
Amounts reclassified from accumulated other comprehensive income	-77	-564	-57,150
Total other comprehensive income (loss)	16,303	-39,656	-44,383
Comprehensive income at the end of the period	-10,910	-27,213	12,443
Securities Available for Sale
Changes in accumulated other comprehensive income by component
Comprehensive income at the beginning of the period	-26,983	11,677	56,269
Other comprehensive income (loss)	18,139	-38,124	12,542
Amounts reclassified from accumulated other comprehensive income	-47	-536	-57,134
Total other comprehensive income (loss)	18,092	-38,660	-44,592
Comprehensive income at the end of the period	-8,891	-26,983	11,677
Net Investment Hedges
Changes in accumulated other comprehensive income by component
Comprehensive income at the beginning of the period	591	-420	-29
Other comprehensive income (loss)	1,945	1,011	-391
Amounts reclassified from accumulated other comprehensive income	0	0	0
Total other comprehensive income (loss)	1,945	1,011	-391
Comprehensive income at the end of the period	2,536	591	-420
Foreign Currency Translation Adjustment
Changes in accumulated other comprehensive income by component
Comprehensive income at the beginning of the period	-1,056	923	392
Other comprehensive income (loss)	-3,704	-1,979	531
Amounts reclassified from accumulated other comprehensive income	0	0	0
Total other comprehensive income (loss)	-3,704	-1,979	531
Comprehensive income at the end of the period	-4,760	-1,056	923
Recognized Postretirement Prior Service Cost and Transition Obligation
Changes in accumulated other comprehensive income by component
Comprehensive income at the beginning of the period	235	263	194
Other comprehensive income (loss)	0	0	85
Amounts reclassified from accumulated other comprehensive income	-30	-28	-16
Total other comprehensive income (loss)	-30	-28	69
Comprehensive income at the end of the period	$205	$235	$263