Investors Bancorp (ISBC) 10-K 29 Feb 16 2015 FY Annual report Financial data

Document And Entity Information

Document And Entity Information - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Feb. 23, 2016	Jun. 30, 2015
Document And Entity Information [Abstract]
Entity Registrant Name	Investors Bancorp, Inc.
Entity Central Index Key	1,594,012
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-K
Document Period End Date	Dec. 31, 2015
Document Fiscal Year Focus	2,015
Document Fiscal Period Focus	FY
Amendment Flag	false
Entity Common Stock, Shares Outstanding		328,014,181
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Public Float			$ 3,940

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
ASSETS
Cash and cash equivalents	$ 148,904	$ 230,961
Securities available-for-sale, at estimated fair value	1,304,697	1,197,924
Securities held-to-maturity, net (estimated fair value of $1,888,686 and $1,609,365 at December 31, 2015 and 2014, respectively)	1,844,223	1,564,479
Loans receivable, net	16,661,133	14,887,570
Loans held-for-sale	7,431	6,868
Stock in the Federal Home Loan Bank	178,437	151,287
Accrued interest receivable	58,563	55,267
Other real estate owned	6,283	7,839
Office properties and equipment, net	172,519	160,899
Net deferred tax asset	237,367	231,898
Bank owned life insurance	159,152	161,609
Goodwill and Intangible assets	105,311	106,705
Other assets	4,664	10,333
Total assets	20,888,684	18,773,639
Liabilities:
Deposits	14,063,656	12,172,326
Borrowed funds	3,263,090	2,766,104
Advance payments by borrowers for taxes and insurance	108,721	69,893
Other liabilities	141,570	187,461
Total liabilities	$ 17,577,037	$ 15,195,784
Commitments and contingencies
Stockholders’ equity:
Preferred stock, $0.01 par value, 100,000,000 authorized shares; none issued	$ 0	$ 0
Common stock, $0.01 par value, 1,000,000,000 shares authorized; 359,070,852 issued at December 31, 2015 and 2014; 334,894,181 and 358,012,895 outstanding at December 31, 2015 and 2014, respectively	3,591	3,591
Additional paid-in capital	2,785,503	2,864,406
Retained earnings	936,040	836,639
Treasury stock, at cost; 24,176,671and 1,057,957 shares at December 31, 2015 and 2014, respectively	(295,412)	(11,131)
Unallocated common stock held by the employee stock ownership plan	(90,250)	(93,246)
Accumulated other comprehensive loss	(27,825)	(22,404)
Total stockholders’ equity	3,311,647	3,577,855
Total liabilities and stockholders’ equity	$ 20,888,684	$ 18,773,639

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Statement of Financial Position [Abstract]
Held-to-maturity securities, estimated fair value	$ 1,888,686	$ 1,609,365
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	100,000,000	100,000,000
Preferred stock, shares issued	0	0
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	1,000,000,000	1,000,000,000
Common stock, shares issued	359,070,852	359,070,852
Common stock, shares outstanding	334,894,181	358,012,895
Treasury stock, shares	24,176,671	1,057,957

Consolidated Statements of Inco

Consolidated Statements of Income - USD ($) $ in Thousands	3 Months Ended				12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Interest and dividend income:
Loans receivable and loans held-for-sale					$ 663,424	$ 603,438	$ 504,622
Securities:
Equity					123	115	61
Government-sponsored enterprise obligations					45	46	9
Mortgage-backed securities					55,096	44,183	28,057
Municipal bonds and other debt					5,929	5,667	5,873
Interest-bearing deposits					225	552	49
Federal Home Loan Bank stock					6,881	6,861	6,397
Total interest and dividend income	$ 188,138	$ 186,897	$ 181,529	$ 175,159	731,723	660,862	545,068
Interest expense:
Deposits					71,414	59,206	49,969
Borrowed Funds					65,225	59,685	59,673
Total interest expense	37,322	35,623	32,977	30,717	136,639	118,891	109,642
Net interest income	150,816	151,274	148,552	144,442	595,084	541,971	435,426
Provision for loan losses	5,000	5,000	7,000	9,000	26,000	37,500	50,500
Net interest income after provision for loan losses	145,816	146,274	141,552	135,442	569,084	504,471	384,926
Non-interest income
Fees and service charges					17,119	19,399	18,804
Income on bank owned life insurance					3,948	4,652	2,898
Gain on loans, net					7,786	5,257	8,748
Gain on securities transactions, net					1,036	1,546	772
Impairment losses on investment securities					0	0	(939)
Non-credit related gains recognized in comprehensive income					0	0	(38)
Net impairment losses on investment securities recognized in earnings					0	0	(977)
Gain on sale of other real estate owned, net					1,631	809	1,451
Other income					8,605	10,198	4,875
Total non-interest income	8,700	11,306	11,585	8,534	40,125	41,861	36,571
Non-interest expense
Compensation and fringe benefits					186,320	172,068	128,765
Advertising and promotional expense					10,988	12,238	8,602
Office occupancy and equipment expense					50,865	49,668	39,226
Federal deposit insurance premiums					9,050	14,390	14,950
Stationery, printing, supplies and telephone					4,372	4,238	3,395
Professional fees					16,104	14,672	11,154
Data processing service fees					22,366	25,333	19,844
Contribution to charitable foundation					0	20,000	0
Other operating expenses					28,267	27,253	19,775
Total non-interest expenses	85,666	85,921	79,836	76,909	328,332	339,860	245,711
Income before income tax expense	68,850	71,659	73,301	67,067	280,877	206,472	175,786
Income tax expense	24,448	22,865	26,939	25,120	99,372	74,751	63,755
Net income	$ 44,402	$ 48,794	$ 46,362	$ 41,947	$ 181,505	$ 131,721	$ 112,031
Basic and Diluted earnings per share (usd per share)	$ 0.14	$ 0.15	$ 0.14	$ 0.12	$ 0.55	$ 0.38	$ 0.40
Weighted average shares outstanding
Basic (shares)					329,763,527	344,389,259	279,632,558
Diluted (shares)					332,933,448	347,731,571	283,035,844

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Statement of Comprehensive Income [Abstract]
Net income	$ 181,505	$ 131,721	$ 112,031
Other comprehensive (loss) income, net of tax:
Change in funded status of retirement obligations	(1,455)	(5,042)	10
Unrealized (loss) gain on securities available-for-sale	(4,933)	5,952	(12,827)
Net loss on securities reclassified from available for sale to held to maturity	0	0	(7,242)
Accretion of loss on securities reclassified to held to maturity	1,448	1,726	988
Unrealized gain on security reclassified from held-to-maturity to available for sale	0	0	138
Reclassification adjustment for security gains included in net income	(1,547)	(138)	(405)
Noncredit related component of other-than-temporary impairment on security	0	0	22
Other-than-temporary impairment accretion on debt securities	1,066	794	1,227
Total other comprehensive (loss) income	(5,421)	3,292	(18,089)
Total comprehensive income	$ 176,084	$ 135,013	$ 93,942

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Common stock	Additional paid-in capital	Retained earnings	Treasury stock	Unallocated Common Stock Held by ESOP	Accumulated other comprehensive loss	Common stockAdditional paid-in capital	Common stockRetained earnings	Common stockTreasury stock
Balance at Dec. 31, 2012	$ 1,066,817	$ 1,356	$ 533,034	$ 644,923	$ (73,692)	$ (31,197)	$ (7,607)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	112,031			112,031
Other comprehensive loss, net of tax	(18,089)						(18,089)
Common stock issues to finance acquisition	179,171	163	179,008
Purchase of treasury stock	(1,531)				(1,531)
Treasury stock allocated to restricted stock plan	0		(55)	13	42
Compensation cost for stock options and restricted stock	3,478		3,478
Net tax benefit from stock-based compensation	1,262		1,262
Option exercise	10,637		2,502		8,135
Cash dividend paid	(22,404)			(22,404)
ESOP shares allocated or committed to be released	2,955		1,537			1,418
Balance at Dec. 31, 2013	1,334,327	1,519	720,766	734,563	(67,046)	(29,779)	(25,696)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	131,721			131,721
Other comprehensive loss, net of tax	3,292						3,292
Common stock issues to finance acquisition	22,000		22,000
Purchase of treasury stock	(13,523)				(13,523)
Treasury stock allocated to restricted stock plan	0		(390)	258	132
Compensation cost for stock options and restricted stock	13,701		13,701
Conversion of Investors Bancorp, MHC	2,093,719	2,140	2,091,579
Purchase by ESOP		66	66,108			(66,174)
Net tax benefit from stock-based compensation	3,710		3,710
Treasury stock retired		(143)	(64,126)		64,269
Contribution of MHC	12,652			12,652
Option exercise	13,810	9	8,764		5,037
Cash dividend paid	(42,555)			(42,555)
ESOP shares allocated or committed to be released	5,001		2,294			2,707	0
Balance at Dec. 31, 2014	3,577,855	3,591	2,864,406	836,639	(11,131)	(93,246)	(22,404)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	181,505			181,505
Other comprehensive loss, net of tax	(5,421)						(5,421)
Purchase of treasury stock	(382,922)				(382,922)
Treasury stock allocated to restricted stock plan	0		(85,897)	5,472	80,425
Compensation cost for stock options and restricted stock	(9,220)		9,220
Net tax benefit from stock-based compensation	2,985		2,985
Option exercise	10,119		(9,045)		19,164
Stock Issued During Period, Value, Share-based Compensation, Forfeited								$ 1,129	$ (181)	$ (948)
Cash dividend paid	(87,395)
ESOP shares allocated or committed to be released	5,701		2,705			2,996
Balance at Dec. 31, 2015	$ 3,311,647	$ 3,591	$ 2,785,503	$ 936,040	$ (295,412)	$ (90,250)	$ (27,825)

Consolidated Statements of Sto7

Consolidated Statements of Stockholders' Equity (Parenthetical)	12 Months Ended
	Dec. 31, 2014$ / sharesshares
Purchase of treasury stock, shares	1,295,193
Initial public stock offering (shares)	213,963,274
Employee stock ownership plan	6,617,421
Shares, retired	14,293,439
Dividends paid per share (usd per share) | $ / shares	$ 0.12

Consolidated Statements Of Cash

Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Cash flows from operating activities:
Net income	$ 181,505	$ 131,721	$ 112,031
Adjustments to reconcile net income to net cash provided by operating activities:
Contribution of stock to charitable foundation	0	10,000	0
ESOP and stock-based compensation expense	14,921	18,702	6,433
Amortization of premiums and accretion of discounts on securities, net	13,943	10,173	9,735
Amortization of premiums and accretion of fees and costs on loans, net	(10,122)	(1,794)	10,517
Amortization of intangible assets	3,350	3,806	2,115
Provision for loan losses	26,000	37,500	50,500
Depreciation and amortization of office properties and equipment	13,930	13,151	8,540
Gain on securities, net	(1,036)	(1,546)	(772)
Other-than-temporary impairment losses on securities	0	0	977
Mortgage loans originated for sale	(238,608)	(150,099)	(379,806)
Proceeds from mortgage loan sales	590,636	186,747	405,973
Gain on sales of mortgage loans, net	(5,258)	(2,832)	(6,207)
Gain on sale of other real estate owned	(1,631)	(809)	(1,451)
Gain on bargain purchase of acquisitions	0	(1,482)	0
Income on bank owned life insurance	(3,948)	(4,652)	(2,898)
(Increase) decrease in accrued interest receivable	(3,296)	(7,100)	1,496
Deferred tax benefit	(3,180)	(9,786)	(20,818)
Decrease (increase) in other assets	4,245	4,425	(6,741)
(Decrease) increase in other liabilities	(48,317)	41,263	(13,530)
Total adjustments	351,629	145,667	64,063
Net cash provided by operating activities	533,134	277,388	176,094
Cash flows from investing activities:
Purchases of loans receivable	(198,623)	(233,856)	(1,054,395)
Net originations of loans receivable	(1,990,008)	(1,650,629)	(778,049)
Proceeds from sale of loans held for investment	49,938	2,425	184,668
Gain on disposition of loans held for investment	(2,528)	(2,425)	(2,541)
Net proceeds from sale of foreclosed real estate	7,104	7,614	10,833
Purchases of mortgage-backed securities held to maturity	(526,095)	(909,421)	(202,821)
Purchases of debt securities held-to-maturity	(56,242)	(20,835)	(9,729)
Purchases of mortgage-backed securities available-for-sale	(375,605)	(587,952)	(295,897)
Proceeds from paydowns/maturities on mortgage-backed securities held-to-maturity	260,039	167,886	80,438
Proceeds from paydowns on equity securities available for sale	2,954	430	148
Proceeds from paydowns/maturities on debt securities held-to-maturity	28	12,596	20,159
Proceeds from calls/maturities on debt securities held-to-maturity	2,977	0	0
Proceeds from maturities of Municipal Bonds	37,505	0	0
Proceeds from paydowns/maturities on mortgage-backed securities available-for-sale	249,729	173,661	284,726
Proceeds from sales of mortgage-backed securities held-to-maturity	0	19,177	0
Proceeds from sales of mortgage-backed securities available-for-sale	0	37,682	401,573
Proceeds from maturity of US Government and Agency Obligations available-for-sale	0	3,000	0
Proceeds from sale of equity securities available for sale	0	13,411	24,540
Redemption of equity securities available-for-sale	0	164	108
Proceeds from redemptions of Federal Home Loan Bank stock	157,342	143,707	143,081
Purchases of Federal Home Loan Bank stock	(184,492)	(116,403)	(161,866)
Purchases of office properties and equipment	(25,550)	(31,655)	(24,544)
Death benefit proceeds from bank owned life insurance	6,405	5,455	0
Cash received from MHC for merger	0	11,307	0
Cash received, net of cash consideration paid for acquisitions	0	17,917	118,246
Net cash used in investing activities	(2,585,122)	(2,936,744)	(1,261,322)
Cash flows from financing activities:
Net increase in deposits	1,891,330	1,198,843	608,801
Net proceeds from sale of common stock	0	2,149,893	0
Loan to ESOP for purchase of common stock	0	(66,174)	0
(Repayments) proceeds of funds borrowed under other repurchase agreements	(10,000)	(98,205)	143,205
Net increase (decrease) in other borrowings	506,986	(508,150)	426,347
Net increase in advance payments by borrowers for taxes and insurance	38,828	1,979	14,447
Dividends paid	(87,395)	(42,555)	(22,404)
Exercise of stock options	10,119	13,810	10,637
Purchase of treasury stock	(382,922)	(13,523)	(1,531)
Net tax benefit from stock-based compensation	2,985	3,710	1,262
Net cash provided by financing activities	1,969,931	2,639,628	1,180,764
Net (decrease) increase in cash and cash equivalents	(82,057)	(19,728)	95,536
Cash and cash equivalents at beginning of year	230,961	250,689	155,153
Cash and cash equivalents at end of year	148,904	230,961	250,689
Non-cash investing activities:
Real estate acquired through foreclosure	4,448	6,404	4,512
Transfer of loans to loans held for sale	347,955	32,411	0
Cash paid during the year for:
Interest	135,930	118,140	109,527
Income taxes	88,169	85,796	83,918
Non-cash assets acquired:
Investment securities available for sale	0	50,347	381,950
Loans	0	195,062	990,970
Goodwill and other intangible assets, net	0	1,853	9,782
Other assets	0	21,343	78,527
Total non-cash assets acquired	0	268,605	1,461,229
Liabilities assumed:
Deposits	0	254,672	1,341,153
Borrowings	0	5,185	92,070
Other liabilities	0	3,184	20,509
Total liabilities assumed	0	263,041	1,453,732
Net non-cash assets acquired	0	5,564	7,497
Common stock issued for acquisitions	$ 0	$ 0	$ 179,171

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2015
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies The following significant accounting and reporting policies of Investors Bancorp, Inc. and subsidiaries (collectively, the Company) conform to U.S. generally accepted accounting principles (GAAP), and are used in preparing and presenting these consolidated financial statements. (a) Basis of Presentation The consolidated financial statements are composed of the accounts of Investors Bancorp, Inc. and its wholly owned subsidiaries, including Investors Bank (Bank). All significant intercompany accounts and transactions have been eliminated in consolidation. Certain reclassifications have been made in the consolidated financial statements to conform with current year classifications. In the opinion of management, all the adjustments (consisting of normal and recurring adjustments) necessary for the fair presentation of the consolidated financial condition and the consolidated results of operations for the periods presented have been included. The results of operations and other data presented for the years ended December 31, 2015 , 2014 and 2013 are not necessarily indicative of the results of operations that may be expected for subsequent years. In January 1997, the Bank completed a Plan of Mutual Holding Company Reorganization, utilizing the multi-tier mutual holding company structure. In a series of steps, the Bank formed a Delaware-chartered stock corporation (Investors Bancorp, Inc.) which owned 100% of the common stock of the Bank and formed a New Jersey-chartered mutual holding company (Investors Bancorp, MHC) which initially owned all of the common stock of Investors Bancorp, Inc. On October 11, 2005 , Investors Bancorp, Inc. completed an initial public stock offering. See Note 2. On May 7, 2014, Investors Bancorp, MHC, Investors Bancorp, Inc. and the Bank completed the Plan of Conversion and Reorganization of the Mutual Holding Company (the “Plan”) in which the Bank reorganized from a two-tier mutual holding company structure to a fully public stock holding company structure. The Company raised net proceeds of $2.15 billion by selling a total of 219,580,695 shares of common stock at $10.00 per share in the second step stock offering and issued 1,000,000 shares of common stock to the Investors Charitable Foundation. Concurrent with the completion of the stock offering, each share of Old Investors Bancorp common stock owned by public stockholders (stockholders other than Investors Bancorp, MHC) was exchanged for 2.55 shares of Company common stock. A total of 137,560,968 shares of Company common stock were issued in the exchange. The conversion was accounted for as a capital raising transaction by entities under common control. The historical financial results of Investors Bancorp, MHC are immaterial to the results of the Company and therefore upon completion of the conversion, the net assets of Investors Bancorp, MHC were merged into the Company and are reflected as an increase to stockholders' equity. In addition, the second step conversion resulted in the accelerated vesting of all outstanding stock awards as of the conversion date. The withholding of shares for payment of taxes with respect to these awards resulted in treasury stock of 1,101,694 shares. As a result of the conversion, all share information has been revised to reflect the 2.55 - to- one exchange ratio. Financial information presented in this Form 10-K is derived in part from the consolidated financial statements of Old Investors Bancorp and subsidiaries. See Note 2. The preparation of financial statements in conformity with GAAP requires us to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the dates of the financial statements and the reported amounts of revenues and expenses during the reporting periods. The estimate of our allowance for loan losses, the valuation of mortgage servicing rights (MSR), the valuation of deferred tax assets, impairment judgments regarding goodwill, and fair value and impairment of securities are particularly critical because they involve a higher degree of complexity and subjectivity and require estimates and assumptions about highly uncertain matters. Actual results may differ from our estimates and assumptions. The current economic environment has increased the degree of uncertainty inherent in these material estimates. Business Investors Bancorp, Inc.’s primary business is holding the common stock of the Bank and a loan to the Investors Bank Employee Stock Ownership Plan. The Bank provides banking services to customers primarily through branch offices in New Jersey and New York. The Bank is subject to competition from other financial institutions and is subject to the regulations of certain federal and state regulatory authorities and undergoes periodic examinations by those regulatory authorities. (b) Cash Equivalents Cash equivalents consist of cash on hand, amounts due from banks and interest-bearing deposits in other financial institutions. The Company is required by the Federal Reserve System to maintain cash reserves equal to a percentage of certain deposits. The reserve requirement totaled $43.4 million at December 31, 2015 and $39.1 million at December 31, 2014. (c) Securities Securities include securities held-to-maturity and securities available-for-sale. Management determines the appropriate classification of securities at the time of purchase. If management has the positive intent not to sell and the Company would not be required to sell prior to maturity, they are classified as held-to-maturity securities. Such securities are stated at amortized cost, adjusted for unamortized purchase premiums and discounts. Securities in the available-for-sale category are debt and mortgage-backed securities which the Company may sell prior to maturity, and all marketable equity securities. Available-for-sale securities are reported at fair value with any unrealized appreciation or depreciation, net of tax effects, reported as accumulated other comprehensive income/loss in stockholders’ equity. Discounts and premiums on securities are accreted or amortized using the level-yield method over the estimated lives of the securities, including the effect of prepayments. Realized gains and losses are recognized when securities are sold or called using the specific identification method. The Company periodically evaluates the security portfolio for other-than-temporary impairment. Other-than-temporary impairment means the Company believes the security’s impairment is due to factors that could include its inability to pay interest or dividends, its potential for default, and/or other factors. In accordance with the Financial Accounting Standards Board (“FASB”) Accounting Standard Codification (“ASC”) Topic 320, “Investments — Debt and Equity Securities” , when a held to maturity or available for sale debt security is assessed for other-than-temporary impairment, the Company has to first consider (a) whether it intends to sell the security, and (b) whether it is more likely than not that the Company will be required to sell the security prior to recovery of its amortized cost basis. If one of these circumstances applies to a security, an other-than-temporary impairment loss is recognized in the statement of income equal to the full amount of the decline in fair value below amortized cost. If neither of these circumstances applies to a security, but the Company does not expect to recover the entire amortized cost basis, an other-than-temporary impairment loss has occurred that must be separated into two categories: (a) the amount related to credit loss, and (b) the amount related to other factors. In assessing the level of other-than-temporary impairment attributable to credit loss, the Company compares the present value of cash flows expected to be collected with the amortized cost basis of the security. The portion of the total other-than-temporary impairment related to credit loss is recognized in earnings, while the amount related to other factors is recognized in other comprehensive income. The total other-than-temporary impairment loss is presented in the statement of income, less the portion recognized in other comprehensive income. When a debt security becomes other-than-temporarily impaired, its amortized cost basis is reduced to reflect the portion of the total impairment related to credit loss. To determine whether a security’s impairment is other-than-temporary, the Company considers factors that include, the duration and severity of the impairment; the Company’s ability and intent to hold security investments until they recover in value (as well as the likelihood of such a recovery in the near term); the Company’s intent to sell security investments; and whether it is more likely than not that the Company will be required to sell such securities before recovery of their individual amortized cost basis less any current-period credit loss. For debt securities, the primary consideration in determining whether impairment is other-than-temporary is whether or not it is probable that current or future contractual cash flows have been or may be impaired. (d) Loans Receivable, Net Loans receivable, other than loans held-for-sale, are stated at unpaid principal balance, adjusted by unamortized premiums and unearned discounts, net deferred origination fees and costs, net purchase accounting adjustments and the allowance for loan losses. Interest income on loans is accrued and credited to income as earned. Premiums and discounts on purchased loans and net loan origination fees and costs are deferred and amortized to interest income over the estimated life of the loan as an adjustment to yield. The allowance for loan losses is increased by the provision for loan losses charged to earnings and is decreased by charge-offs, net of recoveries. The provision for loan losses is based on management’s evaluation of the adequacy of the allowance which considers, among other things, the Company’s past loan loss experience (using the appropriate look-back and loss emergence periods), known and inherent risks in the portfolio, existing adverse situations that may affect the borrower’s ability to repay, estimated value of any underlying collateral and current economic conditions. While management uses available information to recognize estimated losses on loans, future additions may be necessary based on changes in economic or other conditions. In addition, various regulatory agencies, as an integral part of their examination process, periodically review the Company’s allowance for loan losses. Such agencies may require the Company to recognize additions to the allowance based upon their judgments and information available to them at the time of their examinations. A loan is considered delinquent when we have not received a payment within 30 days of its contractual due date. The accrual of income on loans is discontinued when interest or principal payments are 90 days in arrears or when the timely collection of such income is doubtful. Loans on which the accrual of income has been discontinued are designated as non-accrual loans and outstanding interest previously credited is reversed. Interest income on non-accrual loans and impaired loans is recognized in the period collected unless the ultimate collection of principal is considered doubtful. A loan is returned to accrual status when all amounts due have been received and the remaining principal is deemed collectible. Loans are generally charged off after an analysis is completed which indicates that collectability of the full principal balance is in doubt. The Company defines an impaired loan as a loan for which it is probable, based on current information, that the lender will not collect all amounts due under the contractual terms of the loan agreement. The Company evaluates commercial loans with an outstanding balance greater than $1.0 million and on non-accrual status, loans modified in a troubled debt restructuring (“TDR”), and other loans over $1.0 million outstanding balance if management has specific information that it is probable they will not collect all amounts due under the contractual terms of the loan agreement for impairment. Impaired loans are individually evaluated to determine that the loan’s carrying value is not in excess of the fair value of the collateral or the present value of the expected future cash flows. Smaller balance homogeneous loans are evaluated for impairment collectively unless they are modified in a trouble debt restructure. Such loans include residential mortgage loans, consumer loans, and loans not meeting the Company’s definition of impaired, and are specifically excluded from impaired loans. Purchased Credit-Impaired ("PCI") loans, are loans acquired at a discount that is due, in part, to credit quality. PCI loans are accounted for in accordance with ASC Subtopic 310-30 and are initially recorded at fair value (as determined by the present value of expected future cash flows) with no valuation allowance (i.e., the allowance for loan losses). The difference between the undiscounted cash flows expected at acquisition and the initial carrying amount (fair value) of the PCI loans, or the “accretable yield,” is recognized as interest income utilizing the level-yield method over the life of the loans. Contractually required payments for interest and principal that exceed the undiscounted cash flows expected at acquisition, or the “non-accretable difference,” are not recognized as a yield adjustment, as a loss accrual or a valuation allowance. Reclassifications of the non-accretable difference to the accretable yield may occur subsequent to the loan acquisition dates due to increases in expected cash flows of the loans and result in an increase in yield on a prospective basis. (e) Loans Held-for-Sale Loans held-for-sale are carried at the lower of cost or estimated fair value, as determined on an aggregate basis. Net unrealized losses, if any, are recognized in a valuation allowance through charges to earnings. Premiums and discounts and origination fees and costs on loans held-for-sale are deferred and recognized as a component of the gain or loss on sale. Gains and losses on sales of loans held-for-sale are recognized on settlement dates and are determined by the difference between the sale proceeds and the carrying value of the loans. These transactions are accounted for as sales based on our satisfaction of the criteria for such accounting which provide that, as transferor, we have surrendered control over the loans. (f) Stock in the Federal Home Loan Bank The Bank, as a member of the Federal Home Loan Bank of New York (FHLB), is required to hold shares of capital stock of the FHLB based on our activities, primarily our outstanding borrowings, with the FHLB. The stock is carried at cost, less any impairment. (g) Office Properties and Equipment, Net Land is carried at cost. Office buildings, leasehold improvements and furniture, fixtures and equipment are carried at cost, less accumulated depreciation and amortization. Office buildings and furniture, fixtures and equipment are depreciated using an accelerated basis over the estimated useful lives of the respective assets. Leasehold improvements are amortized using the straight-line method over the terms of the respective leases or the lives of the assets, whichever is shorter. (h) Bank Owned Life Insurance Bank owned life insurance is carried at the amount that could be realized under the Company’s life insurance contracts as of the date of the consolidated balance sheets and is classified as a non-interest earning asset. Increases in the carrying value are recorded as non-interest income in the consolidated statements of income and insurance proceeds received are generally recorded as a reduction of the carrying value. The carrying value consists of cash surrender value of $152.5 million at December 31, 2015 and $155.8 million at December 31, 2014 and a claims stabilization reserve of $6.6 million at December 31, 2015 and $5.8 million at December 31, 2014 . Repayment of the claims stabilization reserve (funds transferred from the cash surrender value to provide for future death benefit payments) and the deferred acquisition costs (costs incurred by the insurance carrier for the policy issuance) is guaranteed by the insurance carrier provided that certain conditions are met at the date of a contract is surrendered. The Company satisfied these conditions at December 31, 2015 and 2014. (i) Intangible Assets Goodwill. Goodwill is presumed to have an indefinite useful life and is tested, at least annually, for impairment at the reporting unit level. Impairment exists when the carrying amount of goodwill exceeds its implied fair value. For purposes of our goodwill impairment testing, we have identified the Bank as a single reporting unit. At December 31, 2015 , the carrying amount of our goodwill totaled $77.6 million . In connection with our annual impairment assessment we applied the guidance in FASB Accounting Standards Update (“ASU”) 2011-08, Intangibles—Goodwill and Other (Topic 350): Testing Goodwill for Impairment, which permits an entity to make a qualitative assessment of whether it is more likely than not that a reporting unit’s fair value is less than its carrying amount before applying the two-step goodwill impairment test. For the year ended December 31, 2015 , the Company’s qualitative assessment concluded that it was not more likely than not that the fair value of the reporting unit is less than its carrying amount and, therefore, the two-step goodwill impairment test was not required. Mortgage Servicing Rights . The Company recognizes as separate assets the rights to service mortgage loans. The right to service loans for others is generally obtained through the sale of loans with servicing retained. The initial asset recognized for originated mortgage servicing rights (“MSR”) is measured at fair value. The fair value of MSR is estimated by reference to current market values of similar loans sold with servicing released. MSR are amortized in proportion to and over the period of estimated net servicing income. We apply the amortization method for measurements of our MSR. MSR are assessed for impairment based on fair value at each reporting date. MSR impairment, if any, is recognized in a valuation allowance through charges to earnings as a component of fees and service charges. Increases in the fair value of impaired MSR are recognized only up to the amount of the previously recognized valuation allowance. Fees earned for servicing loans are reported as income when the related mortgage loan payments are collected. Core Deposit Premiums . Core deposit premiums represent the intangible value of depositor relationships assumed in purchase acquisitions and are amortized on an accelerated basis over 10 years. The Company periodically evaluates the value of core deposit premiums to ensure the carrying amount exceeds it implied fair value. (j) Other Real Estate Owned Real estate owned (REO) consists of properties acquired through foreclosure or deed in lieu of foreclosure. Such assets are carried at the lower of cost or fair value, less estimated selling costs, based on independent appraisals. Write-downs required at the time of acquisition are charged to the allowance for loan losses. Thereafter, decreases in the properties’ estimated fair value which are charged to income along with any additional property maintenance and protection expenses incurred in owning the property. (k) Borrowed Funds Our FHLB borrowings, frequently referred to as advances, are over collateralized by our residential and non residential mortgage portfolios as well as qualified investment securities. The Bank also enters into sales of securities under agreements to repurchase with selected brokers and the FHLB. The securities underlying the agreements are delivered to the counterparty who agrees to resell to the Bank the identical securities at the maturity or call of the agreement. These agreements are recorded as financing transactions, as the Bank maintains effective control over the transferred securities, and no gain or loss is recognized. The dollar amount of the securities underlying the agreements continues to be carried in the Bank’s securities portfolio. The obligations to repurchase the securities are reported as a liability in the consolidated balance sheets. (l) Income Taxes The Company records income taxes in accordance with Accounting Standard Codification (ASC) 740 “Income Taxes,” as amended, using the asset and liability method. Accordingly, deferred tax assets and liabilities: (i) are recognized for the expected future tax consequences of events that have been recognized in the financial statements or tax returns; (ii) are attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases; and (iii) are measured using enacted tax rates expected to apply in the years when those temporary differences are expected to be recovered or settled. Where applicable, deferred tax assets are reduced by a valuation allowance for any portions determined not likely to be realized. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income tax expense in the period of enactment. The valuation allowance is adjusted, by a charge or credit to income tax expense, as changes in facts and circumstances warrant. The Company recognizes accrued interest and penalties related to unrecognized tax benefits, where applicable, in income tax expense. (m) Employee Benefits The Company has a defined benefit pension plan which covers all employees who satisfy the eligibility requirements. The Company participates in a multiemployer plan. Costs of the pension plan are based on the contributions required to be made to the plan. The Company has two Supplemental Employee Retirement Plans (SERPs). The SERPs are a nonqualified, defined benefit plans which provide benefits to certain eligible employees of the Company whose benefits and/or contributions under the pension plan are limited by the Internal Revenue Code. The Company also has a nonqualified, defined benefit plan which provides benefits to its directors. The SERP and the directors’ plan are unfunded and the costs of the plans are recognized over the period that services are provided. The Company has a 401(k) plan covering substantially all employees. The Company matches 50% of the first 6% contributed by participants and recognizes expense as its contributions are made. The employee stock ownership plan (ESOP) is accounted for in accordance with the provisions of Statement ASC 718-40, “Employers’ Accounting for Employee Stock Ownership Plans.” The funds borrowed by the ESOP from the Company to purchase the Company’s common stock are being repaid from the Bank’s contributions over a period of up to 30 years. The Company’s common stock not yet allocated to participants is recorded as a reduction of stockholders’ equity at cost. Compensation expense for the ESOP is based on the market price of the Company’s stock and is recognized as shares are committed to be released to participants due to the repayment of the loan by the ESOP to the Company. The Company recognizes the cost of employee services received in exchange for awards of equity instruments based on the grant-date fair value of those awards in accordance with ASC 718, “Compensation-Stock Compensation”. The Company estimates the per share fair value of option grants on the date of grant using the Black-Scholes option pricing model using assumptions for the expected dividend yield, expected stock price volatility, risk-free interest rate and expected option term. These assumptions are subjective in nature, involve uncertainties and, therefore, cannot be determined with precision. The Black-Scholes option pricing model also contains certain inherent limitations when applied to options that are not traded on public markets. The per share fair value of options is highly sensitive to changes in assumptions. In general, the per share fair value of options will move in the same direction as changes in the expected stock price volatility, risk-free interest rate and expected option term, and in the opposite direction as changes in the expected dividend yield. For example, the per share fair value of options will generally increase as expected stock price volatility increases, risk-free interest rate increases, expected option term increases and expected dividend yield decreases. The use of different assumptions or different option pricing models could result in materially different per share fair values of options. (n) Earnings Per Share Basic earnings per common share, or EPS, are computed by dividing net income by the weighted-average common shares outstanding during the year. The weighted-average common shares outstanding includes the weighted-average number of shares of common stock outstanding less the weighted average number of unvested shares of restricted stock and unallocated shares held by the ESOP. For EPS calculations, ESOP shares that have been committed to be released are considered outstanding. ESOP shares that have not been committed to be released are excluded from outstanding shares on a weighted average basis for EPS calculations. Diluted EPS is computed using the same method as basic EPS, but includes the effect of all potentially dilutive common shares that were outstanding during the period, such as unexercised stock options and unvested shares of restricted stock, calculated using the treasury stock method. When applying the treasury stock method, we add: (1) the assumed proceeds from option exercises; (2) the tax benefit that would have been credited to additional paid-in capital assuming exercise of non-qualified stock options and vesting of shares of restricted stock; and (3) the average unamortized compensation costs related to unvested shares of restricted stock and stock options. We then divide this sum by our average stock price to calculate shares repurchased. The excess of the number of shares issuable over the number of shares assumed to be repurchased is added to basic weighted average common shares to calculate diluted EPS.

Stock Transactions

Stock Transactions	12 Months Ended
	Dec. 31, 2015
Equity [Abstract]
Stock Transactions	Stock Transactions Stock Offering Investors Bancorp, Inc. (the “Company”) is a Delaware corporation that was incorporated in December 2013 to be the successor to Investors Bancorp, Inc. (“Old Investors Bancorp”) upon completion of the mutual-to-stock conversion of Investors Bancorp, MHC, the top tier holding company of Old Investors Bancorp. Old Investors Bancorp completed its initial public stock offering on October 11, 2005 selling 131,649,089 shares, or 43.74% of its outstanding common stock, to subscribers in the offering, including 10,847,883 shares purchased by the ESOP. Upon completion of the initial public offering, Investors Bancorp, MHC, a New Jersey chartered mutual holding company held 165,353,151 shares, or 54.94% of the Company’s outstanding common stock (shares restated to include shares issued in a business combination subsequent to initial public offering). Additionally, the Company contributed $5.2 million in cash and issued 3,949,473 shares of common stock, or 1.32% of its outstanding shares, to Investors Bank Charitable Foundation resulting in a pre-tax expense charge of $20.7 million . Net proceeds from the initial offering were $509.7 million . The Company contributed $255.0 million of the net proceeds to the Bank. In conjunction with the second step conversion, Investors Bancorp, MHC merged into Old Investors Bancorp (and ceased to exist), and Old Investors Bancorp merged into the Company and the Company became its successor under the name Investors Bancorp, Inc. The second step conversion was completed May 7, 2014. The Company raised net proceeds of $2.15 billion by selling a total of 219,580,695 shares of common stock at $10.00 per share in the second step stock offering and issued 1,000,000 shares of common stock to the Investors Charitable Foundation. Concurrent with the completion of the stock offering, each share of Old Investors Bancorp common stock owned by public stockholders (stockholders other than Investors Bancorp, MHC) was exchanged for 2.55 shares of Company common stock. A total of 137,560,968 shares of Company common stock were issued in the exchange. The conversion was accounted for as a capital raising transaction by entities under common control. The historical financial results of Investors Bancorp, MHC are immaterial to the results of the Company and therefore upon completion of the conversion, the net assets of Investors Bancorp, MHC were merged into the Company and are reflected as an increase to stockholders' equity. In addition, the second step conversion resulted in the accelerated vesting of all outstanding stock awards as of the conversion date. The withholding of shares for payment of taxes with respect to these awards resulted in treasury stock of 1,101,694 shares. Stock Repurchase Programs On March 1, 2011, the Company announced its fourth Share Repurchase Program, which authorized the purchase of an additional 10% of its publicly-held outstanding shares of common stock, or 9,885,133 shares. Under the stock repurchase programs, shares of the Company’s common stock could be purchased in the open market and through privately negotiated transactions, from time to time, depending on market conditions. This stock repurchase program commenced upon the completion of the third program on July 25, 2011 . In connection with the second step conversion completed on May 7, 2014, the existing stock repurchase plan was terminated. Under applicable federal regulations, the Company was not permitted to implement a stock repurchase program during the first year following completion of the second-step conversion without prior notice to, and the receipt of a non-objection from, the Federal Reserve Board. On March 16, 2015, the Company announced it had received approval from the Board of Governors of the Federal Reserve System to commence a 5% buyback program prior to the one-year anniversary of the completion of its second step conversion. Accordingly, the Board of Directors authorized the repurchase of 17,911,561 shares. On June 9, 2015, the Company announced its second share repurchase program, which authorized the purchase of an additional 10% of its publicly-held outstanding shares of common stock, or approximately 34,779,211 shares. The new repurchase program commenced immediately upon completion of the first repurchase plan on June 30, 2015. During the year ended December 31, 2015 , the Company purchased 31,576,421 shares at a cost of $382.9 million , or approximately $12.13 per share. During the year ended December 31, 2014 , prior to the second step conversion, the Company purchased 1,295,193 shares at a cost of $13.5 million , or approximately $10.44 per share. The second step conversion on May 7, 2014 resulted in the accelerated vesting of all outstanding stock awards. The withholding of shares for payments of taxes with respect to these awards resulted in the purchase of 1,101,694 shares. The remaining shares are held for general corporate use. Cash Dividend On September 28, 2012, the Company declared its first quarterly cash dividend of $0.02 per share. It was the first dividend since completing its initial public stock offering in October 2005. Since declaring this dividend, the Company has paid a dividend to stockholders in each subsequent quarter.

Business Combinations

Business Combinations	12 Months Ended
	Dec. 31, 2015
Business Combinations [Abstract]
Business Combinations	Business Combinations On January 10, 2014, the Company completed its acquisition of Gateway Community Financial Corp., the federally-chartered holding company for GCF Bank ("Gateway"), which operated 4 branches in Gloucester County, New Jersey. After the purchase accounting adjustments, the Company added $254.7 million in customer deposits and acquired $195.1 million in loans. This transaction generated $1.9 million in core deposit premium. The acquisition was accounted for under the acquisition method of accounting as prescribed by FASB ASC 805 “Business Combinations”, as amended. Under this method of accounting, the purchase price has been allocated to the respective assets acquired and liabilities assumed based on their estimated fair values, net of applicable income tax effects. The acquisition resulted in a bargain purchase gain of $1.5 million , net of tax. In conjunction with the acquisition, Investors Bancorp issued 1,945,079 shares to Investors Bancorp, MHC which was determined using the closing average twenty day stock price of Investors Bancorp's common stock. GCF Bank was merged into the Bank as of the acquisition date. The following table summarizes the estimated fair values of the assets acquired and liabilities assumed at the date of acquisition for Gateway Financial, net of cash consideration paid: At January 10, 2014 (In millions) Cash and cash equivalents, net $ 17.9 Securities available-for-sale 50.3 Loans receivable 195.1 Accrued interest receivable 0.7 Other real estate owned 0.4 Office properties and equipment, net 4.3 Intangible assets 1.9 Other assets 15.9 Total assets acquired 286.5 Deposits (254.7 ) Borrowed funds (5.2 ) Other liabilities (3.1 ) Total liabilities assumed $ (263.0 ) Net assets acquired $ 23.5 The purchase accounting for the Gateway Financial transaction is complete and reflected in the table above and in our consolidated financial statements. Fair Value Measurement of Assets Acquired and Liabilities Assumed Described below are the methods used to determine the fair values of the significant assets acquired and liabilities assumed in the Gateway acquisition based on guidance from ASC 820-10 which defines fair value as the price that would be received to sell an asset or transfer a liability in an orderly transaction between market participants at the measurement date. Securities . The estimated fair values of the investment securities classified as available for sale were calculated utilizing Level 1 inputs. The prices for these instruments are based upon sales of the securities shortly after the acquisition date. The Company reviewed the data and assumptions used in pricing the securities by its third party provider to ensure the highest level of significant inputs are derived from market observable data. Loans. Level 3 inputs were utilized to value the acquired loan portfolio and included the use of present value techniques employing cash flow estimates and the incorporated assumptions that marketplace participants would use in estimating fair values. In instances where reliable market information was not available, the Company used its own assumptions in an effort to determine reasonable fair value. Specifically, the Company utilized three separate fair value analyses we believe a market participant might employ in estimating the entire fair value adjustment required under ASC 820-10. The three separate fair valuation methodologies used are: 1) interest rate loan fair value analysis, 2) general credit fair value adjustment, and 3) specific credit fair value adjustment. To prepare the interest rate fair value analysis, loans were assembled into groupings by characteristics such as loan type, term, collateral and rate. Market rates for similar loans were obtained from various external data sources and reviewed by Company management for reasonableness. The average of these rates was used as the fair value interest rate a market participant would utilize. A present value approach was utilized to calculate the interest rate fair value adjustment. The general credit fair value adjustment was calculated using a two part general credit fair value analysis; 1) expected lifetime losses and 2) estimated fair value adjustment for qualitative factors. The expected lifetime losses were calculated using an average of historical losses of the Company, the acquired banks and peer banks. The adjustment related to qualitative factors was impacted by general economic conditions and the risk related to lack of familiarity with the originator's underwriting process. To calculate the specific credit fair value adjustment the Company reviewed the acquired loan portfolio for loans meeting the definition of an impaired loan as defined by ASC 310-30. Loans meeting this criteria were reviewed by comparing the contractual cash flows to expected collectible cash flows. The aggregate expected cash flows less the acquisition date fair value will result in an accretable yield amount. The accretable yield amount will be recognized over the life of the loans on a level yield basis as an adjustment to yield. Deposits / Core Deposit Premium. Core deposit premium represents the value assigned to demand, interest checking, money market and savings accounts acquired as part of an acquisition. The core deposit premium value represents the future economic benefit, including the present value of future tax benefits, of the potential cost savings from acquiring core deposits as part of an acquisition compared to the cost alternative funding sources and is valued utilizing Level 2 inputs. Certificates of deposit (time deposits) are not considered to be core deposits as they are assumed to have a low expected average life upon acquisition. The fair value of certificates of deposits represents the present value of the certificates' expected contractual payments discounted by market rates for similar CDs and is valued utilizing Level 2 inputs. Borrowed Funds. The present value approach was used to determine the fair value of the borrowed funds acquired during 2014. The fair value of the liability represents the present value of the expected payments using the current rate of a replacement borrowing of the same type and remaining term to maturity and is valued utilizing Level 2 inputs.

Securities

Securities	12 Months Ended
	Dec. 31, 2015
Investments, Debt and Equity Securities [Abstract]
Securities	Securities The following tables present the carrying value, gross unrealized gains and losses and estimated fair value for available-for-sale securities and the amortized cost, net unrealized losses, gross unrecognized gains and losses and estimated fair value for held-to-maturity securities as of the dates indicated: At December 31, 2015 Carrying value Gross unrealized gains Gross unrealized losses Estimated fair value (In thousands) Available-for-sale: Equity securities $ 5,778 733 16 6,495 Mortgage-backed securities: Federal Home Loan Mortgage Corporation 546,652 3,242 2,443 547,451 Federal National Mortgage Association 724,851 4,520 3,299 726,072 Government National Mortgage Association 24,841 1 163 24,679 Total mortgage-backed securities available-for-sale 1,296,344 7,763 5,905 1,298,202 Total available-for-sale securities $ 1,302,122 8,496 5,921 1,304,697 At December 31, 2015 Amortized cost Net unrealized losses (1) Carrying value Gross unrecognized gains (2) Gross unrecognized losses (2) Estimated fair value (In thousands) Held-to-maturity: Debt securities: Government-sponsored enterprises $ 4,232 — 4,232 11 — 4,243 Municipal bonds 43,058 — 43,058 1,307 — 44,365 Corporate and other debt securities 58,358 (23,245 ) 35,113 42,704 77,817 Total debt securities held-to-maturity 105,648 (23,245 ) 82,403 44,022 — 126,425 Mortgage-backed securities: Federal Home Loan Mortgage Corporation 516,841 (2,502 ) 514,339 2,213 3,082 513,470 Federal National Mortgage Association 1,228,845 (2,705 ) 1,226,140 7,305 6,120 1,227,325 Government National Mortgage Association 21,330 — 21,330 125 — 21,455 Federal Housing Authorities 11 — 11 — — 11 Total mortgage-backed securities held-to-maturity 1,767,027 (5,207 ) 1,761,820 9,643 9,202 1,762,261 Total held-to-maturity securities $ 1,872,675 (28,452 ) 1,844,223 53,665 9,202 1,888,686 At December 31, 2014 Carrying value Gross unrealized gains Gross unrealized losses Estimated fair value (In thousands) Available-for-sale: Equity securities $ 6,887 1,636 — 8,523 Mortgage-backed securities: Federal Home Loan Mortgage Corporation 503,268 5,023 1,008 507,283 Federal National Mortgage Association 675,535 7,641 1,184 681,992 Government National Mortgage Association 125 1 — 126 Total mortgage-backed securities available-for-sale 1,178,928 12,665 2,192 1,189,401 Total available-for-sale securities $ 1,185,815 14,301 2,192 1,197,924 At December 31, 2014 Amortized cost Net unrealized losses (1) Carrying Value Gross unrecognized gains (2) Gross unrecognized losses (2) Estimated fair value (In thousands) Held-to-maturity: Debt securities: Government-sponsored enterprises $ 4,388 — 4,388 15 — 4,403 Municipal bonds 24,320 — 24,320 1,001 — 25,321 Corporate and other debt securities 58,487 (25,047 ) 33,440 32,163 367 65,236 Total debt securities held-to-maturity 87,195 (25,047 ) 62,148 33,179 367 94,960 Mortgage-backed securities: Federal Home Loan Mortgage Corporation 504,407 (3,770 ) 500,637 3,561 1,878 502,320 Federal National Mortgage Association 978,261 (3,885 ) 974,376 11,629 1,218 984,787 Government National Mortgage Association 27,136 — 27,136 — 20 27,116 Federal housing authorities 182 — 182 — — 182 Total mortgage-backed securities held-to-maturity 1,509,986 (7,655 ) 1,502,331 15,190 3,116 1,514,405 Total held-to-maturity securities $ 1,597,181 (32,702 ) 1,564,479 48,369 3,483 1,609,365 (1) Net unrealized losses of held-to-maturity corporate and other debt securities represent the other than temporary charge related to other non-credit factors and is being amortized through accumulated other comprehensive income over the remaining life of the securities. For mortgage-backed securities, it represents the net loss on previously designated available-for sale securities transferred to held-to-maturity at fair value and is being amortized through accumulated other comprehensive income over the remaining life of the securities. (2) Unrecognized gains and losses of held-to-maturity securities are not reflected in the financial statements, as they represent fair value fluctuations from the later of: (i) the date a security is designated as held-to-maturity; or (ii) the date that an OTTI charge is recognized on a held-to-maturity security, through the date of the balance sheet. A portion of the Company’s securities are pledged to secure borrowings. The contractual maturities of mortgage-backed securities are generally less than 20 years; with effective lives expected to be shorter due to anticipated prepayments. Expected maturities may differ from contractual maturities due to prepayment or early call privileges of the issuer, therefore, mortgage-backed securities are not included in the following table. The amortized cost and estimated fair value of debt securities at December 31, 2015 , by contractual maturity, are shown below. December 31, 2015 Carrying Value Estimated fair value (In thousands) Due in one year or less $ 40,136 40,136 Due after one year through five years 2,363 2,375 Due after five years through ten years — — Due after ten years 39,904 83,914 Total $ 82,403 126,425 Gross unrealized losses on securities and the estimated fair value of the related securities, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position at December 31, 2015 and December 31, 2014 , was as follows: December 31, 2015 Less than 12 months 12 months or more Total Estimated fair value Unrealized losses Estimated fair value Unrealized losses Estimated fair value Unrealized losses (In thousands) Available-for-sale: Equity Securities $ 4,692 16 — — 4,692 16 Mortgage-backed securities: Federal Home Loan Mortgage Corporation $ 263,255 2,443 — — 263,255 2,443 Federal National Mortgage Association 375,792 2,850 14,821 449 390,613 3,299 Government National Mortgage Association 24,874 163 24,874 163 Total mortgage-backed securities available-for-sale 663,921 5,456 14,821 449 678,742 5,905 Total available-for-sale securities $ 668,613 5,472 14,821 449 683,434 5,921 Held-to-maturity: Mortgage-backed securities: Federal Home Loan Mortgage Corporation 342,702 2,804 4,887 278 347,589 3,082 Federal National Mortgage Association 547,326 5,477 29,013 643 576,339 6,120 Total mortgage-backed securities held-to-maturity 890,028 8,281 33,900 921 923,928 9,202 Total held-to-maturity securities $ 890,028 8,281 33,900 921 923,928 9,202 Total $ 1,558,641 13,753 48,721 1,370 1,607,362 15,123 December 31, 2014 Less than 12 months 12 months or more Total Estimated fair value Unrealized losses Estimated fair value Unrealized losses Estimated fair value Unrealized losses (In thousands) Available-for-sale: Mortgage-backed securities: Federal Home Loan Mortgage Corporation 76,525 426 60,394 582 136,919 1,008 Federal National Mortgage Association 67,017 50 52,519 1,134 119,536 1,184 Total mortgage-backed securities available-for-sale 143,542 476 112,913 1,716 256,455 2,192 Total available-for-sale securities 143,542 476 112,913 1,716 256,455 2,192 Held-to-maturity: Debt securities: Corporate and other debt securities 674 40 233 327 907 367 Mortgage-backed securities: Federal Home Loan Mortgage Corporation 199,962 1,043 47,892 835 247,854 1,878 Federal National Mortgage Association 145,520 371 37,517 847 183,037 1,218 Government National Mortgage Association 27,116 20 — — 27,116 20 Total mortgage-backed securities held-to-maturity 372,598 1,434 85,409 1,682 458,007 3,116 Total held-to-maturity securities $ 373,272 1,474 85,642 2,009 458,914 3,483 Total $ 516,814 1,950 198,555 3,725 715,369 5,675 At December 31, 2015 gross unrealized losses primarily relate to our mortgage-backed-security portfolio which is comprised of securities issued by U.S. Government Sponsored Enterprises. The fair values of these securities have been negatively impacted by the recent increase in intermediate-term market interest rates. The gross unrealized losses at December 31, 2015 also relate to our corporate and other debt securities (trust preferred securities) whose estimated fair value has been adversely impacted by the economic environment, an increase in current market rates, wider credit spreads and credit deterioration subsequent to the purchase of these securities. At December 31, 2015 , corporate and other debt securities include a portfolio of collateralized debt obligations backed by pooled trust preferred securities ("TruPS"), principally issued by banks and to a lesser extent insurance companies, real estate investment trusts, and collateralized debt obligations. While all were investment grade at purchase, securities classified as non-investment grade at December 31, 2015 had an amortized cost and estimated fair value of $33.2 million and $71.1 million , respectively. Fair value is derived from considering specific assumptions, including terms of the TruPS structure, events of deferrals, defaults and liquidations, the projected cashflow for principal and interest payments, and discounted cash flow modeling. Other-Than-Temporary Impairment (“OTTI”) We conduct a quarterly review and evaluation of the securities portfolio to determine if the value of any security has declined below its cost or amortized cost, and whether such decline is other-than-temporary. If a determination is made that a debt security is other-than-temporarily impaired, the Company will estimate the amount of the unrealized loss that is attributable to credit and all other non-credit related factors. The credit related component will be recognized as an other-than-temporary impairment charge in non-interest income. The non-credit related component will be recorded as an adjustment to accumulated other comprehensive income, net of tax. With the assistance of a valuation specialist, we evaluate the credit and performance of each underlying issuer of our trust preferred securities by deriving probabilities and assumptions for default, recovery and prepayment/amortization for the expected cash flows for each security. At December 31, 2015 and 2014, management deemed that the present value of projected cash flows for each security was greater than the book value and did not recognize any additional OTTI charges for the periods ended December 31, 2015 and 2014. At December 31, 2013, the discounted cash flow projected for one of the Company's pooled trust preferred securities fell below its adjusted book value. Based on the review of underlying collateral, the credit of this security continued to deteriorate and therefore the Company recorded net other-than-temporary impairment ("OTTI") charge of $977,000 for the year ended December 31, 2013. At December 31, 2015 , the security had a fair value of $94,000 . At December 31, 2015 , non-credit related OTTI recorded on the previously impaired pooled trust preferred securities was $23.2 million ( $13.8 million after-tax) and is being accreted into income over the estimated remaining life of the securities. The following table presents the changes in the credit loss component of the impairment loss of debt securities that the Company has written down for such loss as an other-than-temporary impairment recognized in earnings. For the Years Ended December 31, 2015 2014 2013 (In thousands) Balance of credit related OTTI, beginning of period $ 108,817 112,235 114,514 Additions: Initial credit impairments — — — Subsequent credit impairments — — 977 Reductions: Accretion of credit loss impairment due to an increase in expected cash flows (3,804 ) (3,418 ) (3,256 ) Reduction for securities sold or paid off during the period (4,813 ) — — Balance of credit related OTTI, end of period $ 100,200 108,817 112,235 The credit loss component of the impairment loss represents the difference between the present value of expected future cash flows and the amortized cost basis of the securities prior to considering credit losses. The beginning balance represents the credit loss component for debt securities for which other-than-temporary impairment occurred prior to the period presented. If other-than-temporary impairment is recognized in earnings for credit impaired debt securities, they would be presented as additions in two components based upon whether the current period is the first time a debt security was credit impaired (initial credit impairment) or is not the first time a debt security was credit impaired (subsequent credit impairments). The credit loss component is reduced if the Company sells, intends to sell or believes it will be required to sell previously credit impaired debt securities. Additionally, the credit loss component is reduced if (i) the Company receives cash flows in excess of what it expected to receive over the remaining life of the credit impaired debt security, (ii) the security matures or (iii) the security is fully written down. Realized Gains and Losses Gains and losses on the sale of all securities are determined using the specific identification method. For the year ended December 31, 2015 , the Company received proceeds of $2.6 million on an equity security from the available-for-sale portfolio resulting in a gross realized gain of $1.5 million . For the year ended December 31, 2015 , the Company recognized gains on available-for-sale securities of $145,000 related to capital distributions of equity securities from the available-for-sale portfolio. For the year ended December 31, 2015 , there were no sales of securities from held-to-maturity portfolio, however for the year ended December 31, 2015 , the Company recognized a loss of $646,000 on a TruP security which was entirely liquidated by its Trustee. For the year ended December 31, 2014 , the Company recognized net gains on available-for-sale securities of $619,000 , of which $145,000 were related to capital distributions of equity securities from the available-for-sale portfolio. In December 2013, regulatory agencies adopted a rule on the treatment of certain collateralized debt obligations backed by trust preferred securities to implement sections of the Dodd-Frank Wall Street Reform and Consumer Protection Act, known as the Volcker Rule. As a result of the evaluation of the impact of the Volcker Rule, the Company reclassified one trust preferred security to available-for-sale. The Company sold the security for the year ended December 31, 2014 , resulting in gross realized gains of $474,000 . For the year ended December 31, 2014 total proceeds of securities from the held-to-maturity portfolio were $19.5 million , which resulted in gross realized gains of $927,000 . For the year ended December 31, 2014 , sales of mortgage back securities from the held-to-maturity portfolio, which had a book value of $18.3 million resulted in gross realized gains of $877,000 . These securities met the criteria of principal pay downs under 85% of the original investment amount and therefore did not result in a tainting of the held-to-maturity portfolio. The Company sells securities when market pricing presents, in management’s assessment, an economic benefit that outweighs holding such securities, and when smaller balance securities become cost prohibitive to carry. In addition, for the year ended December 31, 2014 , the Company recognized a gain of $50,000 on a TruP security which was entirely liquidated by its Trustee. For the year ended December 31, 2014 there were no losses recognized. For the year ended December 31, 2013 , proceeds from sales of securities from available-for-sale portfolio were $56.0 million , which resulted in gross realized gains of $846,100 and $162,300 of gross realized losses as well as $88,600 of net gains on capital distributions of equity securities. In addition, at December 31, 2013 the Company recognized a net other-than-temporary charge of $977,000 for one of the pooled trust preferred security falling below its adjusted book value. There were no sales from the held-to-maturity portfolio for the year ended December 31, 2013 .

Loans Receivable, Net

Loans Receivable, Net	12 Months Ended
	Dec. 31, 2015
Receivables [Abstract]
Loans Receivable, Net	Loans Receivable, Net The detail of the loan portfolio as of December 31, 2015 and December 31, 2014 was as follows: December 31, December 31, (In thousands) Multi-family loans $ 6,255,904 5,048,477 Commercial real estate loans 3,821,950 3,139,824 Commercial and industrial loans 1,044,329 544,402 Construction loans 224,057 143,664 Total commercial loans 11,346,240 8,876,367 Residential mortgage loans 5,037,898 5,764,896 Consumer and other loans 496,103 440,500 Total loans excluding PCI loans 16,880,241 15,081,763 PCI loans 11,089 17,789 Net unamortized premiums/discounts and deferred loan fees/costs (1) (11,692 ) (11,698 ) Allowance for loan losses (218,505 ) (200,284 ) Net loans $ 16,661,133 14,887,570 (1) Included in unamortized premiums/discounts and deferred loan fees/costs are accretable purchase accounting adjustments in connection with loans acquired. Purchased Credit-Impaired Loans Purchased Credit-Impaired ("PCI") loans, are loans acquired at a discount that is due, in part, to credit quality. PCI loans are accounted for in accordance with ASC Subtopic 310-30 and are initially recorded at fair value as determined by the present value of expected future cash flows with no valuation allowance reflected in the allowance for loan losses. The following table presents information regarding the estimates of the contractually required payments, the cash flows expected to be collected and the estimated fair value of the PCI loans acquired in the Gateway Financial acquisition as of January 10, 2014: January 10, 2014 (In thousands) Contractually required principal and interest $ 4,172 Contractual cash flows not expected to be collected (non-accretable difference) (1,024 ) Expected cash flows to be collected 3,148 Interest component of expected cash flows (accretable yield) (216 ) Fair value of acquired loans $ 2,932 The following table presents changes in the accretable yield for PCI loans during the years ended December 31, 2015 and 2014 : Years Ended December 31, 2015 2014 (In thousands) Balance, beginning of period $ 971 4,154 Acquisitions — 216 Accretion (1) (522 ) (3,399 ) Net reclassification from non-accretable difference — — Balance, end of period $ 449 971 (1) Includes the removal of $1.9 million accretable mark on PCI loans sold during the year ended December 31, 2014 . This transfer had no impact on income for the year ended December 31, 2014 . An analysis of the allowance for loan losses is summarized as follows: Years Ended December 31, 2015 2014 2013 (In thousands) Balance at beginning of the period $ 200,284 173,928 142,172 Loans charged off (12,216 ) (18,244 ) (22,610 ) Recoveries 4,437 7,100 3,866 Net charge-offs (7,779 ) (11,144 ) (18,744 ) Provision for loan losses 26,000 37,500 50,500 Balance at end of the period $ 218,505 200,284 173,928 The allowance for loan losses is the estimated amount considered necessary to cover credit losses inherent in the loan portfolio at the balance sheet date. The allowance is established through the provision for loan losses that is charged against income. In determining the allowance for loan losses, we make significant estimates and therefore, have identified the allowance as a critical accounting policy. The methodology for determining the allowance for loan losses is considered a critical accounting policy by management because of the high degree of judgment involved, the subjectivity of the assumptions used, and the potential for changes in the economic environment that could result in changes to the amount of the recorded allowance for loan losses. The allowance for loan losses has been determined in accordance with U.S. GAAP, under which we are required to maintain an allowance for probable losses at the balance sheet date. We are responsible for the timely and periodic determination of the amount of the allowance required. We believe that our allowance for loan losses is adequate to cover specifically identifiable losses, as well as estimated losses inherent in our portfolio for which certain losses are probable but not specifically identifiable. Loans acquired are marked to fair value on the date of acquisition with no valuation allowance reflected in the allowance for loan losses. In conjunction with the quarterly evaluation of the adequacy of the allowance for loan loss, the Company performs an analysis on acquired loans to determine whether or not there has been subsequent deterioration in relation to those loans. If deterioration has occurred, the Company will include these loans in their calculation of the allowance for loan loss. For the year ended December 31, 2015 , the Company recorded charge offs related to PCI loans acquired of $388,000 . Management performs a quarterly evaluation of the adequacy of the allowance for loan losses. The analysis of the allowance for loan losses has two components: specific and general allocations. Specific allocations are made for loans determined to be impaired. A loan is deemed to be impaired if it is a commercial loan with an outstanding balance greater than $1.0 million and on non-accrual status, loans modified in a troubled debt restructuring (“TDR”), and other commercial loans greater than $1.0 million if management has specific information that it is probable they will not collect all amounts due under the contractual terms of the loan agreement. Impairment is measured by determining the present value of expected future cash flows or, for collateral-dependent loans, the fair value of the collateral adjusted for market conditions and selling expenses. The general allocation is determined by segregating the remaining loans, including those loans not meeting the Company’s definition of an impaired loan, by type of loan, risk rating (if applicable) and payment history. In addition, the Company's residential portfolio is subdivided between fixed and adjustable rate loans as adjustable rate loans are deemed to be subject to more credit risk if interest rates rise. The loss factors used are based on the Company's historical loss experience over a look-back period determined to provide the appropriate amount of data to accurately estimate expected losses as of period end. Additionally, management assesses the loss emergence period for the expected losses of each loan segment and adjusts each historical loss factor accordingly. The loss emergence period is the estimated time from the date of a loss event (such as a personal bankruptcy) to the actual recognition of the loss (typically via the first full or partial loan charge-off), and is determined based upon a study of the Company's past loss experience by loan segment. The loss factors may also be adjusted to account for qualitative or environmental factors that are likely to cause estimated credit losses inherent in the portfolio to differ from historical loss experience. This evaluation is based on among other things, loan and delinquency trends, general economic conditions, geographic concentrations, lending policies and procedures and industry and peer comparisons, but is inherently subjective as it requires material estimates that may be susceptible to significant revisions based upon changes in economic and real estate market conditions. Actual loan losses may be different than the allowance for loan losses we have established which could have a material negative effect on our financial results. On a quarterly basis, management reviews the current status of various loan assets in order to evaluate the adequacy of the allowance for loan losses. In this evaluation process, specific loans are analyzed to determine their potential risk of loss. Loans determined to be impaired are evaluated for potential loss exposure. Any shortfall results in a recommendation of a a charge-off or specific allowance or charge-off if the likelihood of loss is evaluated as probable. To determine the adequacy of collateral on a particular loan, an estimate of the fair value of the collateral is based on the most current appraised value available for real property or a discounted cash flow analysis on a business. This appraised value for real property is then reduced to reflect estimated liquidation expenses. The allowance contains reserves identified as unallocated. These reserves reflect management's attempt to ensure that the overall allowance reflects a margin for imprecision and the uncertainty that is inherent in estimates of probable credit losses. Our primary lending emphasis has been the origination of commercial real estate loans, multi-family loans, commercial and industrial loans and the origination and purchase of residential mortgage loans. We also originate home equity loans and home equity lines of credit. These activities resulted in a concentration of loans secured by real estate property and businesses located in New Jersey and New York. Based on the composition of our loan portfolio, we believe the primary risks are increases in interest rates, a decline in the general economy, and declines in real estate market values in New Jersey, New York and surrounding states. Any one or combination of these events may adversely affect our loan portfolio resulting in increased delinquencies, loan losses and future levels of loan loss provisions. As a substantial amount of our loan portfolio is collateralized by real estate, appraisals of the underlying value of property securing loans are critical in determining the amount of the allowance required for specific loans. Assumptions for appraisal valuations are instrumental in determining the value of properties. Negative changes to appraisal assumptions could significantly impact the valuation of a property securing a loan and the related allowance determined. The assumptions supporting such appraisals are carefully reviewed to determine that the resulting values reasonably reflect amounts realizable on the related loans. For commercial real estate, multi-family and construction loans, the Company obtains an appraisal for all collateral dependent loans upon origination. An updated appraisal is obtained annually for loans rated substandard or worse with a balance of $500,000 or greater. An updated appraisal is obtained bi-annually for loans rated special mention with a balance of $2.0 million or greater. This is done in order to determine the specific reserve or charge off needed. As part of the allowance for loan loss process, the Company reviews each collateral dependent commercial real estate loan previously classified as non-accrual and/or impaired and assesses whether there has been an adverse change in the collateral value supporting the loan. The Company utilizes information from its commercial lending officers and its credit department and loan workout department’s knowledge of changes in real estate conditions in our lending area to identify if possible deterioration of collateral value has occurred. Based on the severity of the changes in market conditions, management determines if an updated appraisal is warranted or if downward adjustments to the previous appraisal are warranted. If it is determined that the deterioration of the collateral value is significant enough to warrant ordering a new appraisal, an estimate of the downward adjustments to the existing appraised value is used in assessing if additional specific reserves are necessary until the updated appraisal is received. For homogeneous residential mortgage loans, the Company’s policy is to obtain an appraisal upon the origination of the loan and an updated appraisal in the event a loan becomes 90 days delinquent. Thereafter, the appraisal is updated every two years if the loan remains in non-performing status and the foreclosure process has not been completed. Management adjusts the appraised value of residential loans to reflect estimated selling costs and declines in the real estate market. Management believes the potential risk for outdated appraisals for impaired and other non-performing loans has been mitigated due to the fact that the loans are individually assessed to determine that the loan’s carrying value is not in excess of the fair value of the collateral. Loans are generally charged off after an analysis is completed which indicates that collectability of the full principal balance is in doubt. Our allowance for loan losses reflects probable losses considering, among other things, the economic conditions, the actual growth and change in composition of our loan portfolio, the level of our non-performing loans and our charge-off experience. We believe the allowance for loan losses reflects the inherent credit risk in our portfolio. Although we believe we have established and maintained the allowance for loan losses at adequate levels, additions may be necessary if the current economic environment deteriorates. Management uses the best information available; however, the level of the allowance for loan losses remains an estimate that is subject to significant judgment and short-term change. In addition, the Federal Deposit Insurance Corporation and the New Jersey Department of Banking and Insurance, as an integral part of their examination process, will periodically review our allowance for loan losses. Such agencies may require us to recognize adjustments to the allowance based on their judgments about information available to them at the time of their examination. The following tables present the balance in the allowance for loan losses and the recorded investment in loans by portfolio segment and based on impairment method as of the years ended December 31, 2015 and 2014 : December 31, 2015 Multi- Family Loans Commercial Real Estate Loans Commercial and Industrial Loans Construction Loans Residential Mortgage Loans Consumer and Other Loans Unallocated Total (Dollars in thousands) Allowance for loan losses: Beginning balance-December 31, 2014 $ 71,147 44,030 20,759 6,488 47,936 3,347 6,577 200,284 Charge-offs (284 ) (1,021 ) (516 ) (466 ) (9,526 ) (403 ) — (12,216 ) Recoveries 445 807 295 317 2,295 278 — 4,437 Provision 16,915 3,183 20,047 455 (9,262 ) (67 ) (5,271 ) 26,000 Ending balance-December 31, 2015 $ 88,223 46,999 40,585 6,794 31,443 3,155 1,306 218,505 Individually evaluated for impairment $ — — 2,409 — 1,773 9 — 4,191 Collectively evaluated for impairment 88,223 46,999 38,176 6,794 29,670 3,146 1,306 214,314 Loans acquired with deteriorated credit quality — — — — — — — Balance at December 31, 2015 $ 88,223 46,999 40,585 6,794 31,443 3,155 1,306 218,505 Loans: Individually evaluated for impairment $ 3,219 18,941 9,395 2,504 22,539 389 — 56,987 Collectively evaluated for impairment 6,252,685 3,803,009 1,034,934 221,553 5,015,359 495,714 — 16,823,254 Loans acquired with deteriorated credit quality — 7,149 56 1,786 1,645 453 — 11,089 Balance at December 31, 2015 $ 6,255,904 3,829,099 1,044,385 225,843 5,039,543 496,556 — 16,891,330 December 31, 2014 Multi- Family Loans Commercial Real Estate Loans Commercial and Industrial Loans Construction Loans Residential Mortgage Loans Consumer and Other Loans Unallocated Total (Dollars in thousands) Allowance for loan losses: Beginning balance-December 31, 2013 $ 42,103 46,657 9,273 8,947 51,760 2,161 13,027 173,928 Charge-offs (323 ) (6,147 ) (2,447 ) (640 ) (7,715 ) (972 ) — (18,244 ) Recoveries 3,784 201 516 799 1,783 17 — 7,100 Provision 25,583 3,319 13,417 (2,618 ) 2,108 2,141 (6,450 ) 37,500 Ending balance-December 31, 2014 $ 71,147 44,030 20,759 6,488 47,936 3,347 6,577 200,284 Individually evaluated for impairment $ — 274 — — 1,865 — — 2,139 Collectively evaluated for impairment 71,147 43,756 20,759 6,488 46,071 3,347 6,577 198,145 Loans acquired with deteriorated credit quality — — — — — — — — Balance at December 31, 2014 $ 71,147 44,030 20,759 6,488 47,936 3,347 6,577 200,284 Loans: Individually evaluated for impairment $ 4,111 22,995 3,310 6,798 23,285 — — 60,499 Collectively evaluated for impairment 5,044,366 3,116,829 541,092 136,866 5,741,611 440,500 — 15,021,264 Loans acquired with deteriorated credit quality 637 7,329 56 4,732 4,581 454 — 17,789 Balance at December 31, 2014 $ 5,049,114 3,147,153 544,458 148,396 5,769,477 440,954 — 15,099,552 The Company categorizes loans into risk categories based on relevant information about the ability of borrowers to service their debt such as: current financial information, historical payment experience, credit documentation, public information and current economic trends, among other factors. For non-homogeneous loans, such as commercial and commercial real estate loans the Company analyzes the loans individually by classifying the loans as to credit risk and assesses the probability of collection for each type of class. This analysis is performed on a quarterly basis. The Company uses the following definitions for risk ratings: Pass - “Pass” assets are well protected by the current net worth and paying capacity of the obligor (or guarantors, if any) or by the fair value, less cost to acquire and sell, of any underlying collateral in a timely manner. Watch - A "Watch" asset has all the characteristics of a Pass asset but warrant more than the normal level of supervision. These loans may require more detailed reporting to management because some aspects of underwriting may not conform to policy or adverse events may have affected or could affect the cash flow or ability to continue operating profitably, provided, however, the events do not constitute an undue credit risk. Residential loans delinquent 30 - 59 days are considered Watch. Special Mention - A “Special Mention” asset has potential weaknesses that deserve management’s close attention. If left uncorrected, these potential weaknesses may result in deterioration of the repayment prospects for the asset or in the institution’s credit position at some future date. Special Mention assets are not adversely classified and do not expose an institution to sufficient risk to warrant adverse classification. Residential loans delinquent 60 - 89 days are considered special mention. Substandard - A “Substandard” asset is inadequately protected by the current worth and paying capacity of the obligor or by the collateral pledged, if any. Assets so classified must have a well-defined weakness, or weaknesses that jeopardize the liquidation of the debt. They are characterized by the distinct possibility that the institution will sustain some loss if the deficiencies are not corrected. Residential loans delinquent 90 days or greater are considered substandard. Doubtful - An asset classified “Doubtful” has all the weaknesses inherent in one classified substandard with the added characteristic that the weaknesses make collection or liquidation in full highly questionable and improbable on the basis of currently known facts, conditions, and values. Loss - An asset or portion thereof, classified “Loss” is considered uncollectible and of such little value that its continuance on the institution’s books as an asset, without establishment of a specific valuation allowance or charge-off, is not warranted. This classification does not necessarily mean that an asset has no recovery or salvage value; but rather, there is much doubt about whether, how much, or when the recovery will occur. As such, it is not practical or desirable to defer the write-off. The following tables present the risk category of loans as of December 31, 2015 and December 31, 2014 by class of loans excluding PCI loans: December 31, 2015 Pass Watch Special Mention Substandard Doubtful Loss Total (In thousands) Commercial loans: Multi-family $ 5,876,425 325,414 17,033 37,032 — — 6,255,904 Commercial real estate 3,411,876 331,429 38,265 40,380 — — 3,821,950 Commercial and industrial 793,527 223,474 13,782 13,546 — — 1,044,329 Construction 207,499 12,833 — 3,725 — — 224,057 Total commercial loans 10,289,327 893,150 69,080 94,683 — — 11,346,240 Residential mortgage 4,930,961 24,584 13,796 68,557 — — 5,037,898 Consumer and other 482,715 3,987 427 8,974 — — 496,103 Total $ 15,703,003 921,721 83,303 172,214 — — 16,880,241 December 31, 2014 Pass Watch Special Mention Substandard Doubtful Loss Total (In thousands) Commercial loans: Multi-family $ 4,710,124 247,921 62,886 27,546 — — 5,048,477 Commercial real estate 2,757,949 276,660 29,248 75,967 — — 3,139,824 Commercial and industrial 405,021 110,374 20,321 8,686 — — 544,402 Construction 134,356 2,228 2,075 5,005 — — 143,664 Total commercial loans 8,007,450 637,183 114,530 117,204 — — 8,876,367 Residential mortgage 5,641,184 22,059 7,657 93,996 — — 5,764,896 Consumer and other 431,314 3,987 1,006 4,193 — — 440,500 Total $ 14,079,948 663,229 123,193 215,393 — — 15,081,763 The following tables present the payment status of the recorded investment in past due loans as of December 31, 2015 and December 31, 2014 by class of loans excluding PCI loans: December 31, 2015 30-59 Days 60-89 Days Greater than 90 Days Total Past Due Current Total Loans Receivable (In thousands) Commercial loans: Multi-family $ 14,236 — 1,886 16,122 6,239,782 6,255,904 Commercial real estate 4,171 352 6,429 10,952 3,810,998 3,821,950 Commercial and industrial 957 — 4,386 5,343 1,038,986 1,044,329 Construction — — 792 792 223,265 224,057 Total commercial loans 19,364 352 13,493 33,209 11,313,031 11,346,240 Residential mortgage 27,092 14,956 68,560 110,608 4,927,290 5,037,898 Consumer and other 3,987 427 8,976 13,390 482,713 496,103 Total $ 50,443 15,735 91,029 157,207 16,723,034 16,880,241 December 31, 2014 30-59 Days 60-89 Days Greater than 90 Days Total Past Due Current Total Loans Receivable (In thousands) Commercial loans: Multi-family $ 698 239 2,989 3,926 5,044,551 5,048,477 Commercial real estate 6,566 778 13,940 21,284 3,118,540 3,139,824 Commercial and industrial 792 395 2,903 4,090 540,312 544,402 Construction — — 4,345 4,345 139,319 143,664 Total commercial loans 8,056 1,412 24,177 33,645 8,842,722 8,876,367 Residential mortgage 23,712 8,900 75,610 108,222 5,656,674 5,764,896 Consumer and other 1,334 1,006 4,211 6,551 433,949 440,500 Total $ 33,102 11,318 103,998 148,418 14,933,345 15,081,763 The following table presents non-accrual loans excluding PCI loans at the dates indicated: December 31, 2015 December 31, 2014 # of loans amount # of loans amount (Dollars in thousands) Non-accrual: Multi-family 4 $ 3,467 2 $ 2,989 Commercial real estate 37 10,820 36 13,940 Commercial and industrial 17 9,225 11 2,903 Construction 4 792 7 4,345 Total commercial loans 62 24,304 56 24,177 Residential and consumer 500 91,122 406 84,182 Total non-accrual loans 562 $ 115,426 462 $ 108,359 Included in the non-accrual table above are TDR loans whose payment status is current but the Company has classified as non-accrual as the loans have not maintained their current payment status for six consecutive months under the restructured terms and therefore do not meet the criteria for accrual status. As of December 31, 2015 , these loans are comprised of 15 residential and consumer TDR loans totaling $3.4 million , 2 commercial and industrial TDR loans totaling $2.2 million , 2 commercial real estate TDR loans totaling $240,000 and 1 multifamily totaling $1.0 million . There were 11 residential TDR loans totaling $3.3 million which were also 30 - 89 days delinquent and classified as non-accrual, 1 commercial and industrial TDR for $360,000 which was 30 - 89 days delinquent and classified as non-accrual and 5 commercial real estate TDR loans for $2.3 million which were 30 - 89 days delinquent and classified as non-accrual. As of December 31, 2014 , these loans are comprised of 5 residential TDR loans totaling $1.5 million . There were 10 residential TDR loans totaling $2.9 million which were also 30 - 89 days delinquent and classified as non-accrual. The Company has no loans past due 90 days or more delinquent that are still accruing interest. PCI loans are excluded from non-accrual loans, as they are recorded at fair value based on the present value of expected future cash flows. As of December 31, 2015 , PCI loans with a carrying value of $11.1 million included $9.0 million of which were current and $2.1 of which were 90 days or more delinquent. As of December 31, 2014 , PCI loans with a carrying value of $17.8 million included $9.2 million of which were current and $8.6 million of which were 90 days or more delinquent. At December 31, 2015 and 2014 , loans meeting the Company’s definition of an impaired loan were primarily collateral dependent loans which totaled $57.0 million and $60.5 million , respectively, with allocations of the allowance for loan losses of $4.2 million and $2.1 million for the periods ending December 31, 2015 and 2014 . During the years ended December 31, 2015 and 2014 , interest income received and recognized on these loans totaled $3.8 million and $2.5 million , respectively. The following tables present loans individually evaluated for impairment by portfolio segment as of December 31, 2015 and December 31, 2014 : December 31, 2015 Recorded Investment Unpaid Principal Balance Related Allowance Average Recorded Investment Interest Income Recognized (In thousands) With no related allowance: Multi-family $ 3,219 6,806 — 2,871 119 Commercial real estate 18,941 27,961 — 19,025 1,136 Commercial and industrial 5,155 5,160 — 3,575 200 Construction 2,504 6,412 — 4,288 226 Total commercial loans 29,819 46,339 — 29,759 1,681 Residential mortgage and consumer 8,020 12,433 — 7,611 463 With an allowance recorded: Multi-family — — — — — Commercial real estate — — — — — Commercial and industrial 4,240 4,271 2,409 4,389 194 Construction — — — — — Total commercial loans 4,240 4,271 2,409 4,389 194 Residential mortgage and consumer 14,908 13,695 1,782 16,424 476 Total: Multi-family 3,219 6,806 — 2,872 119 Commercial real estate 18,941 27,961 — 19,025 1,136 Commercial and industrial 9,395 9,431 2,409 7,964 394 Construction 2,504 6,412 — 4,288 226 Total commercial loans 34,059 50,610 2,409 34,149 1,875 Residential mortgage and consumer 22,928 26,128 1,782 24,035 939 Total impaired loans $ 56,987 76,738 4,191 58,184 2,814 December 31, 2014 Recorded Investment Unpaid Principal Balance Related Allowance Average Recorded Investment Interest Income Recognized (In thousands) With no related allowance: Multi-family $ 4,111 7,846 — 4,746 135 Commercial real estate 19,901 23,601 — 17,056 879 Commercial and industrial 3,310 3,310 — 1,985 152 Construction 6,798 9,292 — 13,609 410 Total commercial loans 34,120 44,049 — 37,396 1,576 Residential mortgage 6,755 8,830 — 6,606 370 With an allowance recorded: Multi-family — — — — — Commercial real estate 3,094 4,760 274 3,106 72 Commercial and industrial — — — — — Construction — — — — — Total commercial loans 3,094 4,760 274 3,106 72 Residential mortgage 16,530 16,882 1,865 16,547 507 Total: Multi-family 4,111 7,846 — 4,746 135 Commercial real estate 22,995 28,361 274 20,162 951 Commercial and industrial 3,310 3,310 — 1,985 152 Construction 6,798 9,292 — 13,609 410 Total commercial loans 37,214 48,809 274 40,502 1,648 Residential mortgage and consumer 23,285 25,712 1,865 23,153 877 Total impaired loans $ 60,499 74,521 2,139 63,655 2,525 The average recorded investment is the annual average calculated based upon the ending quarterly balances. The interest income recognized is the year to date interest income recognized on a cash basis. Troubled Debt Restructurings On a case-by-case basis, the Company may agree to modify the contractual terms of a borrower’s loan to remain competitive and assist customers who may be experiencing financial difficulty, as well as preserve the Company’s position in the loan. If the borrower is experiencing financial difficulties and a concession has been made at the time of such modification, the loan is classified as a troubled debt restructured loan ("TDR"). Substantially all of our troubled debt restructured loan modifications involve lowering the monthly payments on such loans through either a reduction in interest rate below a market rate, an extension of the term of the loan, or a combination of these two methods. These modifications rarely result in the forgiveness of principal or accrued interest. In addition, we frequently obtain additional collateral or guarantor support when modifying commercial loans. Restructured loans remain on non accrual status until there has been a sustained period of repayment performance (generally six consecutive months of payments) and both principal and interest are deemed collectible. The following tables present the total troubled debt restructured loans at December 31, 2015 and December 31, 2014 . There were three residential PCI loans that were classified as TDRs and are included in the table below at December 31, 2015 . There were no PCI loans classified as a TDR for the period ended December 31, 2014 . December 31, 2015 Accrual Non-accrual Total # of loans Amount # of loans Amount # of loans Amount (Dollars in thousands) Commercial loans: Multi-family — $ — 2 $ 1,580 2 $ 1,580 Commercial real estate 5 13,161 9 5,826 14 18,987 Commercial and industrial 1 640 3 2,586 4 3,226 Construction 1 313 2 405 3 718 Total commercial loans 7 14,114 16 10,397 23 24,511 Residential mortgage and consumer 32 8,375 49 14,553 81 22,928 Total 39 $ 22,489 65 $ 24,950 104 $ 47,439 December 31, 2014 Accrual Non-accrual Total # of loans Amount # of loans Amount # of loans Amount (Dollars in thousands) Commercial loans: Multi-family 2 $ 1,122 — $ — 2 $ 1,122 Commercial real estate 8 15,250 1 3,197 9 18,447 Commercial and industrial 2 1,381 — — 2 1,381 Construction 2 3,066 — — 2 3,066 Total commercial loans 14 20,819 1 3,197 15 24,016 Residential mortgage and consumer 41 14,805 29 8,456 70 23,261 Total 55 $ 35,624 30 $ 11,653 85 $ 47,277 The following table presents information about troubled debt restructurings that occurred during the years ended December 31, 2015 and 2014 : Years Ended December 31, 2015 2014 Number of Loans Pre-modification Recorded Investment Post- modification Recorded Investment Number of Loans Pre-modification Recorded Investment Post- modification Recorded Investment (Dollars in thousands) Troubled Debt Restructings: Multi-family 1 $ 1,115 $ 1,115 — $ — $ — Commercial real estate 4 824 824 3 10,657 7,657 Construction 2 1,508 1,508 — — — Commercial and industrial 2 2,246 2,246 — — — Residential mortgage 19 3,413 3,413 11 3,217 3,217 Post-modification recorded investment represents the net book balance immediately following modification. All TDRs are impaired loans, which are individually evaluated for impairment, as discussed above. Collateral dependent impaired loans classified as TDRs were written down to the estimated fair value of the collateral. There were no charge-offs for collateral dependent TDR during the year ended December 31, 2015 . For the year ended December 31, 2014 there was $3.0 million in charges-offs for collateral dependent TDRs. The allowance for loan losses associated with the TDRs presented in the above tables totaled $1.8 million and $1.9 million for the periods at December 31, 2015 and 2014 , respectively. Residential mortgage loan modifications primarily involved the reduction in loan interest rate and extension of loan maturity dates. All residential loans deemed to be TDRs were modified to reflect a reduction in interest rates to current market rates. Several residential TDRs include step up interest rates in their modified terms which will impact their weighted average yield in the future. Commercial loan modifications which qualified as a TDR comprised of terms of maturity being extended and reduction in interest rates to current market terms. For the year ended December 31, 2015 , commercial loans which qualified as a TDR involved the maturity and payment terms being modified. As of December 31, 2015 and December 31, 2014 , the Company has no additional fundings to any borrowers classified as a troubled debt restructuring. The following table presents information about pre and post modification interest yield for troubled debt restructurings which occurred during the years ended December 31, 2015 and 2014 : Years Ended December 31, 2015 2014 Number of Loans Pre-modification Interest Yield Post- modification Interest Yield Number of Loans Pre-modification Interest Yield Post- modification Interest Yield Troubled Debt Restructings: Multi-family 1 3.88 % 3.88 % — — % — % Commercial real estate 4 4.53 % 5.35 % 3 6.59 % 5.75 % Construction 2 4.97 % 4.97 % — — — Commercial and industrial 2 6.24 % 6.24 % — — — Residential mortgage 19 4.84 % 3.40 % 11 5.35 % 3.90 % Payment defaults for loans modified as TDR during the period ended December 31, 2015 consisted of one construction loan with a recorded investment of $225,000 at December

Office Properties and Equipment

Office Properties and Equipment, Net	12 Months Ended
	Dec. 31, 2015
Property, Plant and Equipment [Abstract]
Office Properties and Equipment, Net	Office Properties and Equipment, Net Office properties and equipment are summarized as follows: December 31, 2015 2014 (In thousands) Land $ 20,569 21,862 Office buildings 87,832 78,808 Leasehold improvements 79,898 66,857 Furniture, fixtures and equipment 77,096 68,420 Construction in process 12,075 17,121 277,470 253,068 Less accumulated depreciation and amortization 104,951 92,169 $ 172,519 160,899 Depreciation and amortization expense for the years ended December 31, 2015 , 2014 and 2013 was $13.9 million , $13.2 million and $8.5 million , respectively.

Goodwill and Intangibles Assets

Goodwill and Intangibles Assets	12 Months Ended
	Dec. 31, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets	Goodwill and Other Intangible Assets The following table summarizes net intangible assets and goodwill at December 31, 2015 and 2014 : December 31, 2015 December 31, 2014 (In thousands) Mortgage servicing rights $ 16,248 14,261 Core deposit premiums 11,332 14,683 Other 160 190 Total other intangible assets 27,740 29,134 Goodwill 77,571 77,571 Goodwill and intangible assets $ 105,311 106,705 The following table summarizes other intangible assets as of December 31, 2015 and December 31, 2014 : Gross Intangible Asset Accumulated Amortization Valuation Allowance Net Intangible Assets (In thousands) December 31, 2015 Mortgage Servicing Rights $ 23,411 (7,042 ) (121 ) 16,248 Core Deposit Premiums 25,058 (13,726 ) — 11,332 Other 300 (140 ) — 160 Total other intangible assets $ 48,769 (20,908 ) (121 ) 27,740 December 31, 2014 Mortgage Servicing Rights $ 23,925 (9,543 ) (121 ) 14,261 Core Deposit Premiums 25,058 (10,375 ) — 14,683 Other 300 (110 ) — 190 Total other intangible assets $ 49,283 (20,028 ) (121 ) 29,134 Mortgage servicing rights are accounted for using the amortization method. Under this method, the Company amortizes the loan servicing asset in proportion to, and over the period of, estimated net servicing revenues. The Company sells loans on a servicing-retained basis. Loans that were sold on this basis, amounted to $2.12 billion and $1.59 billion at December 31, 2015 and December 31, 2014 respectively, all of which relate to residential mortgage loans. At December 31, 2015 and 2014 , the servicing asset, included in intangible assets, had an estimated fair value of $16.2 million and $14.3 million , respectively. For the period ending December 31, 2015 fair value was based on expected future cash flows considering a weighted average discount rate of 10.20% , a weighted average constant prepayment rate on mortgages of 10.80% and a weighted average life of 6.1 years. Core deposit premiums are amortized using an accelerated method and having a weighted average amortization period of 10 years . For the year ended December 31, 2014 , the Company recorded $1.9 million in core deposit premiums resulting from the acquisition of Gateway Financial in January 2014. The following presents the estimated future amortization expense of other intangible assets for the next five years: Mortgage Servicing Rights Core Deposit Premiums Other (In thousands) 2016 $ 473 $ 2,900 $ 30 2017 506 2,441 30 2018 522 1,983 30 2019 538 1,524 30 2020 552 1,109 30

Deposits

Deposits	12 Months Ended
	Dec. 31, 2015
Banking and Thrift [Abstract]
Deposits	Deposits Deposits are summarized as follows: December 31, 2015 2014 Weighted Average Rate Amount % of Total Weighted Average Rate Amount % of Total (In thousands) Checking accounts 0.17 % $ 4,636,025 32.96 % 0.20 % $ 3,892,839 31.98 % Money market deposits 0.67 % 3,861,317 27.46 % 0.71 % 3,390,238 27.85 % Savings 0.29 % 2,150,004 15.29 % 0.27 % 2,318,911 19.05 % Total transaction accounts 0.38 % 10,647,346 75.71 % 0.40 % 9,601,988 78.88 % Certificates of deposit 1.14 % 3,416,310 24.29 % 1.00 % 2,570,338 21.12 % Total Deposits 0.56 % $ 14,063,656 100.00 % 0.53 % $ 12,172,326 100.00 % Scheduled maturities of certificates of deposit are as follows: December 31, 2015 2014 (In thousands) Within one year $ 2,586,076 1,450,655 One to two years 496,288 660,523 Two to three years 167,028 278,190 Three to four years 57,443 74,526 After four years 109,475 106,444 $ 3,416,310 2,570,338 The aggregate amount of certificates of deposit in denominations of $100,000 or more totaled approximately $1.32 billion and $1.19 billion at December 31, 2015 and December 31, 2014 , respectively. Interest expense on deposits consists of the following: For the Years Ended December 31, 2015 2014 2013 (In thousands) Checking accounts $ 9,642 8,755 6,245 Money market deposits 23,562 13,664 7,537 Savings 6,976 6,639 6,320 Certificates of deposit 31,234 30,148 29,867 Total $ 71,414 59,206 49,969

Borrowed Funds

Borrowed Funds	12 Months Ended
	Dec. 31, 2015
Debt Disclosure [Abstract]
Borrowed Funds	Borrowed Funds Borrowed funds are summarized as follows: December 31, 2015 2014 Principal Weighted Average Rate Principal Weighted Average Rate (Dollars in thousands) Funds borrowed under repurchase agreements: FHLB $ 24,383 3.90% $ 25,071 3.90% Other brokers 131,924 1.89% 142,847 2.00% Total funds borrowed under repurchase agreements 156,307 2.21% 167,918 2.28% Other borrowed funds: FHLB advances 3,106,783 2.12% 2,598,186 2.24% Total borrowed funds $ 3,263,090 2.13% $ 2,766,104 2.24% Borrowed funds had scheduled maturities as follows: December 31, 2015 2014 Principal Weighted Average Rate Principal Weighted Average Rate (Dollars in thousands) Within one year $ 500,000 1.99% $ 576,250 2.03% One to two years 249,383 3.00% 325,000 2.79% Two to three years 862,924 2.13% 250,071 3.00% Three to four years 469,782 1.78% 763,597 2.22% Four to five years 650,000 1.99% 444,994 1.78% After five years 531,001 2.30% 406,192 2.18% Total borrowed funds $ 3,263,090 2.13% $ 2,766,104 2.24% Mortgage-backed securities have been sold, subject to repurchase agreements, to the FHLB and various brokers. Mortgage-backed securities sold, subject to repurchase agreements, are held by the FHLB for the benefit of the Company. Repurchase agreements require repurchase of the identical securities. Whole mortgage loans have been pledged to the FHLB as collateral for advances, but are held by the Company. The amortized cost and fair value of the underlying securities used as collateral for securities sold under agreements to repurchase are as follows: December 31, 2015 2014 (Dollars in thousands) Amortized cost of collateral: Mortgage-backed securities $ 475,984 195,890 Total amortized cost of collateral $ 475,984 195,890 Fair value of collateral: Mortgage-backed securities $ 481,401 198,502 Total fair value of collateral $ 481,401 198,502 During the years ended December 31, 2015 , 2014 and 2013, the maximum month-end balance of the repurchase agreements was $163.0 million , $ 261.2 million and $267.7 million , respectively. The average amount of repurchase agreements outstanding during the years ended December 31, 2015 , 2014 and 2013 was $159.4 million , $192.9 million and $165.4 million , respectively, and the average interest rate was 2.25% , 2.02% and 1.50% , respectively. At December 31, 2015 , the Company participated in the FHLB’s Overnight Advance program. This program allows members to borrow overnight up to their maximum borrowing capacity at the FHLB. At December 31, 2015 , our borrowing capacity at the FHLB was $8.78 billion , of which the Company had outstanding borrowings of $3.12 billion and outstanding letters of credit of $1.83 billion . The overnight advances are priced at the federal funds rate plus a spread (generally between 20 and 30 basis points) and re-price daily. In addition, the Bank had an effective commitment for unsecured discretionary overnight borrowings with other institutions totaling $125 million , of which no balance was outstanding at December 31, 2015 .

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The components of income tax expense are as follows: Years Ended December 31, 2015 2014 2013 (In thousands) Current tax expense: Federal $ 87,748 77,029 76,692 State 14,804 7,508 7,881 102,552 84,537 84,573 Deferred tax (benefit) expense: Federal 4,310 (3,846 ) (16,887 ) State (7,490 ) (5,940 ) (3,931 ) (3,180 ) (9,786 ) (20,818 ) Total income tax expense $ 99,372 74,751 63,755 The following table presents the reconciliation between the actual income tax expense and the “expected” amount computed using the applicable statutory federal income tax rate of 35% : Years Ended December 31, 2015 2014 2013 (In thousands) “Expected” federal income tax expense $ 98,307 72,265 61,525 State tax, net 4,753 1,019 2,567 Bank owned life insurance (1,382 ) (1,628 ) (1,014 ) Expiration of loss carryforward — — 645 Change in valuation allowance for federal deferred tax assets — — (645 ) Acquisition related net operating loss (4,076 ) — — ESOP fair market value adjustment 947 349 538 Non-deductible compensation 276 3,334 411 Non-deductible acquisition related expenses — — 297 Expiration of stock options 19 2 — Other 528 (590 ) (569 ) Total income tax expense $ 99,372 74,751 63,755 The temporary differences and loss carryforwards which comprise the deferred tax asset and liability are as follows: December 31, 2015 2014 (In thousands) Deferred tax asset: Employee benefits $ 36,372 30,832 Deferred compensation 1,417 1,332 Premises and equipment 2,262 1,532 Allowance for loan losses 88,894 79,255 Net unrealized loss on securities 10,420 9,101 Net other than temporary impairment loss on securities 42,085 44,225 ESOP 3,695 2,921 Allowance for delinquent interest 13,071 12,379 Fair value adjustments related to acquisitions 31,986 38,309 Charitable contribution carryforward 5,823 5,685 Loan origination costs 7,127 10,821 Intangible assets 45 — Other 1,409 1,969 Gross deferred tax asset 244,606 238,361 Valuation allowance (346 ) (346 ) 244,260 238,015 Deferred tax liability: Intangible assets — 251 Mortgage servicing rights 6,893 5,866 Gross deferred tax liability 6,893 6,117 Net deferred tax asset $ 237,367 231,898 A deferred tax asset is recognized for the estimated future tax effects attributable to temporary differences and carryforwards. The measurement of deferred tax assets is reduced by the amount of any tax benefits that, based on available evidence, are more likely than not to be realized. The ultimate realization of the deferred tax asset is dependent upon the generation of future taxable income during the periods in which those temporary differences and carryforwards become deductible. A valuation allowance is recorded for tax benefits which management has determined are not more likely than not to be realized. In connection with the Company’s second step conversion, a $20.0 million charitable contribution was made to Investors Charitable Foundation. $10.0 million was made in cash at the Bank level, and is expected to be fully realized based on the Bank’s future taxable income. The remaining $10.0 million contribution was made by Investors Bancorp, Inc., and based on the standalone future state taxable income at the Bancorp level, a valuation allowance of $346,000 was established as of December 31, 2014 for the portion of the state tax benefit related to the contribution that is not more likely than not to be realized. At December 31, 2015 the Company's valuation allowance pertaining to the charitable contributions remained at $346,000 . Based upon projections of future taxable income and the ability to carry back losses for two years, management believes it is more likely than not the Company will realize the remaining deferred tax asset. Retained earnings at December 31, 2015 included approximately $45.2 million for which deferred income taxes of approximately $19.2 million have not been provided. The retained earnings amount represents the base year allocation of income to bad debt deductions for tax purposes only. Base year reserves are subject to recapture if the Bank makes certain non-dividend distributions, repurchases any of its stock, pays dividends in excess of tax earnings and profits, or ceases to maintain a bank charter. Under ASC 740, this amount is treated as a permanent difference and deferred taxes are not recognized unless it appears that it will be reduced and result in taxable income in the foreseeable future. Events that would result in taxation of these reserves include failure to qualify as a bank for tax purposes or distributions in complete or partial liquidation. The Company had no unrecognized tax benefits or related interest or penalties at December 31, 2015 and 2014 . The Company files income tax returns in the United States federal jurisdiction and in the states of New Jersey and New York. As of December 31, 2015, the Company was under audit by the IRS in connection with its 2013 federal consolidated tax return, however the Company is no longer subject to federal income tax examination for years prior to 2012. Investors Bank and its affiliates are currently under audit by the New York State Department of Taxation and Finance for tax years 2013 and 2014. The Company is no longer subject to income tax examination by New Jersey and New York for years prior to 2011 and 2012, respectively.

Benefit Plans

Benefit Plans	12 Months Ended
	Dec. 31, 2015
Compensation and Retirement Disclosure [Abstract]
Benefit Plans	Benefit Plans Defined Benefit Pension Plan The Company participates in the Pentegra Defined Benefit Plan for Financial Institutions (“Pentegra DB Plan”), a tax-qualified defined-benefit pension plan. The Pentegra DB Plan’s Employer Identification Number is 13-5645888 and the Plan Number is 333. The Pentegra DB Plan operates as a multi-employer plan for accounting purposes and as a multiple-employer plan under the Employee Retirement Income Security Act of 1974 and the Internal Revenue Code. There are no collective bargaining agreements in place that require contributions to the Pentegra DB Plan. The Pentegra DB Plan is a single plan under Internal Revenue Code Section 413(c) and, as a result, all of the assets stand behind all of the liabilities. Accordingly, under the Pentegra DB Plan contributions made by a participating employer may be used to provide benefits to participants of other participating employers. The funded status (fair value of plan assets divided by funding target) as of July 1, 2015 and 2014 was 99.17% and 107.60% , respectively. The fair value of plan assets reflects any contributions received through June 30, 2015. The Company’s required contribution and pension cost was $9.2 million , $5.3 million and $5.9 million in the years ended December 31, 2015 , 2014 and 2013 , respectively. The accrued pension liability was $727,000 and $672,000 million at December 31, 2015 and 2014 , respectively. The Company’s contributions to the Pentegra DB Plan are not more than 5% of the total contributions to the plan. The Company's expected contribution for the 2016 year is approximately $6.5 million . SERPs, Directors’ Plan and Other Postretirement Benefits Plan The Company has an Executive Supplemental Retirement Wage Replacement Plan ("Wage Replacement Plan") and the Supplemental ESOP and Retirement Plan ("Supplemental ESOP") (collectively, the "SERPs"). The Wage Replacement Plan is a nonqualified, defined benefit plan which provides benefits to certain executives as designated by the Compensation Committee of the Board of Directors. More specifically, the Wage Replacement Plan is designed to provide participants with a normal retirement benefit equal to an annual benefit of 60% of the participant's highest annual base salary and cash inventive (over a consecutive 36-month period within the last 120 consecutive calendar months of employment) reduced by the sum of the benefits provided under the Pentagra DB Plan and the annualized value of their benefits payable under the defined benefit portion of the Supplemental ESOP. The Supplemental ESOP compensates certain executives (as designated by the Compensation Committee of the Board of Directors) participating in the Pentegra DB Plan and the ESOP whose contributions are limited by the Internal Revenue Code. The Company also maintains the Amended and Restated Director Retirement Plan for certain directors, which is a nonqualified, defined benefit plan. This plan was frozen on November 21, 2006 such that no new benefits accrued under, and no new directors were eligible to participate in the plan. The Wage Replacement Plan, Supplemental ESOP and the directors’ plan are unfunded and the costs of the plans are recognized over the period that services are provided. The following table sets forth information regarding the Wage Replacement Plan and the directors’ defined benefit plan: December 31, 2015 2014 (In thousands) Change in benefit obligation: Benefit obligation at beginning of year $ 40,522 29,152 Service cost 3,096 2,319 Interest cost 1,497 1,322 (Gain) loss due to change in mortality assumption (778 ) 3,289 (Gain) loss due to change in discount rate (1,587 ) 4,816 Loss due to demographic changes 6,008 495 Benefits paid (871 ) (871 ) Benefit obligation at end of year 47,887 40,522 Funded status $ (47,887 ) (40,522 ) The unfunded pension benefits of $47.9 million and $40.5 million at December 31, 2015 and 2014 , respectively, are included in other liabilities in the consolidated balance sheets. The components of accumulated other comprehensive loss related to pension plans, on a pre-tax basis, at December 31, 2015 and 2014 , are summarized in the following table. December 31, 2015 2014 (In thousands) Prior service cost $ — 49 Net actuarial gain 19,284 16,923 Total amounts recognized in accumulated other comprehensive income $ 19,284 16,972 The accumulated benefit obligation for the Wage Replacement Plan and directors’ defined benefit plan was $28.6 million and $23.6 million at December 31, 2015 and 2014 , respectively. The measurement date for our SERP and directors’ plan is December 31 for the years ended December 31, 2015 and 2014 . The weighted-average actuarial assumptions used in the plan determinations at December 31, 2015 and 2014 were as follows: December 31, 2015 2014 Discount rate 3.99 % 3.71 % Rate of compensation increase 4.36 % 4.19 % The components of net periodic benefit cost are as follows: Years Ended December 31, 2015 2014 2013 (In thousands) Service cost $ 3,096 2,319 1,799 Interest cost 1,497 1,322 908 Amortization of: Prior service cost 49 98 98 Net gain 1,282 633 660 Total net periodic benefit cost $ 5,924 4,372 3,465 The following are the weighted average assumptions used to determine net periodic benefit cost: Years Ended December 31, 2015 2014 2013 Discount rate 3.71 % 4.53 % 3.56 % Rate of compensation increase 4.19 % 4.00 % 3.87 % Estimated future benefit payments, which reflect expected future service, as appropriate for the next ten calendar years are as follows: Amount (In thousands) 2016 $ 1,175 2017 925 2018 906 2019 885 2020 2,882 2021 through 2025 22,174 401(k) Plan The Company has a 401(k) plan covering substantially all employees providing they meet the eligibility age requirement of age 21. The Company matches 50% of the first 6% contributed by the participants to the 401(k) plan. The Company’s aggregate contributions to the 401(k) plan for the years ended December 31, 2015 , 2014 and 2013 were $2.2 million , $2.0 million and $1.5 million , respectively. Employee Stock Ownership Plan The ESOP is a tax-qualified plan designed to invest primarily in the Company’s common stock that provides employees with the opportunity to receive a funded retirement benefit from the Bank, based primarily on the value of the Company’s common stock. During the Company's initial public stock offering in October 2005 the ESOP was authorized to purchase, and did purchase, 10,847,883 shares of the Company’s common stock at a price of $3.92 per share with the proceeds of a loan from the Company to the ESOP. In connection with the completion of the Company's mutual to stock conversion on May 7, 2014, the ESOP purchased an additional 6,617,421 common shares of stock at a price of $10.00 per share with the proceeds of a loan from the Company to the ESOP. The Company refinanced the outstanding principal and interest balance of $33.9 million and borrowed an additional $66.2 million to purchase the additional shares. The outstanding loan principal balance at December 31, 2015 was $94.9 million . Shares of the Company’s common stock pledged as collateral for the loan are released from the pledge pro-rata for allocation to participants as loan payments are made. At December 31, 2015 , shares allocated to participants were 4,201,759 since the plan inception. ESOP shares that were unallocated or not yet committed to be released totaled 13,263,545 at December 31, 2015 , and had a fair value of $165.0 million . ESOP compensation expense for the years ended December 31, 2015 , 2014 and 2013 was $5.5 million , $5.1 million and $3.0 million , respectively, representing the fair value of shares allocated or committed to be released during the year. The Supplemental ESOP also provides supplemental benefits to certain executives as designated by the Compensation Committee of the Board of Directors who are prevented from receiving the full benefits contemplated by ESOP's benefit formula due to the Internal Revenue Code. During the years ended December 31, 2015 , 2014 and 2013 , compensation expense related to this plan amounted to $656,000 , $568,000 and $782,000 , respectively. Equity Incentive Plan At the annual meeting held on June 9, 2015, stockholders of the Company approved the Investors Bancorp, Inc. 2015 Equity Incentive Plan ("2015 Plan"). On June 23, 2015, the Company granted to directors and certain employees a total of 6,849,832 restricted stock awards and 11,576,612 stock options to purchase Company stock. The restricted stock awards and stock options were issued out of the 2015 Plan, which allows the Company to grant common stock or options to purchase common stock at specific prices to directors and employees of the Company. The 2015 Plan provides for the issuance or delivery of up to 30,881,296 shares ( 13,234,841 restricted stock awards and 17,646,455 stock options) of Investors Bancorp, Inc. common stock. Restricted shares granted under the 2015 Plan vest in equal installments, over the service period generally ranging from 5 to 7 years beginning one year from the date of grant. Additionally, certain restricted shares awarded are performance vesting awards, which may or may not vest depending upon the attainment of certain corporate financial targets. The vesting of restricted stock may accelerate in accordance with the terms of the 2015 Plan. The product of the number of shares granted and the grant date closing market price of the Company's common stock determine the fair value of restricted shares under the 2015 Plan. Management recognizes compensation expense for the fair value of restricted shares on a straight-line basis over the requisite service period. Stock options granted under the 2015 Plan vest in equal installments, over the service period generally ranging from 5 to 7 years beginning one year from the date of grant. The vesting of stock options may accelerate in accordance with the terms of the 2015 Plan. Stock options were granted at an exercise price equal to the fair value of the Company's common stock on the grant date based on the closing market price and have an expiration period of 10 years. The fair value of stock options granted on June 23, 2015 was estimated utilizing the Black-Scholes option pricing model using the following assumptions: Stock Options Granted Weighted average expected life (in years) 7.43 Weighted average risk-free rate of return 1.96 % Weighted average volatility 25.33 % Dividend yield 1.59 % Weighted average fair value of options granted $ 3.12 The weighted average expected life of the stock option represents the period of time that stock options are expected to be outstanding and is estimated using historical data of stock option exercises and forfeitures. The risk-free interest rate is based on the U.S. Treasury yield curve in effect at the time of grant. The expected volatility is based on the historical volatility of the Company's stock. The Company recognizes compensation expense for the fair values of these awards, which have graded vesting, on a straight-line basis over the requisite service period of the awards. The Company applied ASC, 718 “ Compensation- Stock Compensation," ("ASC 718") and began to expense the fair value of all share-based compensation granted over the requisite service periods. ASC 718 requires the Company to report as a financing cash flow the benefits of realized tax deductions in excess of previously recognized tax benefits on compensation expense. In accordance with SEC Staff Accounting Bulletin No. 107 (“SAB 107”), the Company classified share-based compensation for employees and outside directors within “compensation and fringe benefits” in the consolidated statements of income to correspond with the same line item as the cash compensation paid. During the year ended December 31, 2014 , the Compensation and Benefits Committee approved the issuance of an additional 38,250 restricted stock awards and 144,177 stock options to certain officers under the Investors Bancorp, Inc. 2006 Equity Incentive Plan (the "2006 Plan"). During the year ended December 31, 2013 , the Compensation and Benefits Committee approved the issuance of an additional 7,650 restricted stock awards and 504,696 stock options to certain officers under the 2006 Plan. In addition, as part of the Roma Financial acquisition 1,584,235 stock awards were granted for the conversion of outstanding Roma Financial stock awards. These shares had a weighted average exercise price of $6.11 per share and were fully vested upon acquisition. The company will not recognize compensation expense in the future on these awards as they have been accounted for as part of the acquisition. The following table presents the share based compensation expense for the year ended December 31, 2015 2014 and 2013 . Upon completion of the mutual-to-stock conversion of Investors Bancorp, MHC on May 7, 2014, vesting accelerated for both stock options and restricted stock outstanding awards and all applicable expenses were recognized during the period. Years Ended December 31, 2015 2014 2013 (Dollars in thousands) Stock option expense $ 2,905 1,800 365 Restricted stock expense 6,314 11,900 3,100 Total share based compensation expense $ 9,219 13,700 3,465 The following is a summary of the status of the Company’s restricted shares as of December 31, 2015 and changes therein during the year then ended: Number of Shares Awarded Weighted Average Grant Date Fair Value Non-vested at December 31, 2014 — $ — Granted 6,849,832 12.54 Vested — — Forfeited (90,000 ) 12.54 Non-vested at December 31, 2015 6,759,832 $ 12.64 Expected future expenses relating to the non-vested restricted shares outstanding as of December 31, 2015 is $77.6 million over a weighted average period of 5.66 years. The following is a summary of the Company’s stock option activity and related information for its option plan for the year ended December 31, 2015 : Number of Stock Options Weighted Average Exercise Price Weighted Average Remaining Contractual Life (in years) Aggregate Intrinsic Value Outstanding at December 31, 2014 9,092,584 $ 6.06 2.8 $ 46,984 Granted 11,576,611 12.54 9.9 Exercised (1,698,283 ) 5.96 1.6 Forfeited (161,419 ) 12.41 Expired (4,677 ) 9.90 Outstanding at December 31, 2015 18,804,816 $ 10.00 6.8 $ 46,996 Exercisable at December 31, 2015 7,366,289 $ 6.06 1.8 $ 46,975 The fair value of the option grants was estimated on the date of grant using the Black-Scholes option-pricing model with the following weighted average assumptions: December 31, 2015 2014 2013 Expected dividend yield 1.59 % 0.35 % 0.16 % Expected volatility 25.33 % 32.97 % 33.20 % Risk-free interest rate 1.96 % 1.69 % 1.38 % Expected option life 7.4 years 6.5 years 6.5 years The weighted average grant date fair value of options granted during the years ended December 31, 2015 and 2014 was $3.12 and $3.63 per share, respectively. Expected future expense relating to the non-vested options outstanding as of December 31, 2015 is $32.7 million over a weighted average period of 5.74 years .

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies The Company is a defendant in certain claims and legal actions arising in the ordinary course of business. Management and the Company’s legal counsel are of the opinion that the ultimate disposition of these matters will not have a material adverse effect on the Company’s financial condition, results of operations or liquidity. At December 31, 2015 , the Company was obligated under various non-cancelable operating leases on buildings and land used for office space and banking purposes. These operating leases contain escalation clauses which provide for increased rental expense, based primarily on increases in real estate taxes and cost-of-living indices. Rental expense under these leases aggregated approximately $19.2 million , $17.3 million and $15.2 million for the years ended December 31, 2015 , 2014 and 2013 , respectively. The projected annual minimum rental commitments are as follows: Amount (In thousands) 2016 $ 20,310 2017 20,055 2018 19,190 2019 18,588 2020 17,013 Thereafter 120,877 $ 216,033 Financial Transactions with Off-Balance-Sheet Risk and Concentrations of Credit Risk The Company is a party to transactions with off-balance-sheet risk in the normal course of business in order to meet the financing needs of its customers. These transactions consist of commitments to extend credit. These transactions involve, to varying degrees, elements of credit and interest rate risk in excess of the amounts recognized in the accompanying consolidated balance sheet. At December 31, 2015 , the Company had commitments to originate total commercial loans of $566.9 million . Additionally, the Company had commitments to originate residential loans of approximately $57.4 million , commitments to purchase residential loans of $82.7 million and unused home equity and overdraft lines of credit, and undisbursed business and construction loans, totaling approximately $960.5 million . No commitments are included in the accompanying consolidated financial statements. The Company has no exposure to credit loss if the customer does not exercise its rights to borrow under the commitment. The Company uses the same credit policies and collateral requirements in making commitments and conditional obligations as it does for on-balance-sheet loans. Commitments to extend credit are agreements to lend to customers as long as there is no violation of any condition established in the contract. Commitments generally have fixed expiration dates or other termination clauses and may require payment of a fee. Since the commitments may expire without being drawn upon, the total commitment amounts do not necessarily represent future cash requirements. The Company evaluates each customer’s creditworthiness on a case-by-case basis. The amount of collateral obtained if deemed necessary by the Company upon extension of credit is based on management’s credit evaluation of the borrower. Collateral held varies but primarily includes residential properties. The Company principally grants commercial real estate loans, multi-family loans, commercial and industrial loans, construction loans, residential mortgage loans and consumer and other loans to borrowers throughout New Jersey, New York and states in close proximity. Its borrowers’ abilities to repay their obligations are dependent upon various factors, including the borrowers’ income and net worth, cash flows generated by the underlying collateral, value of the underlying collateral and priority of the Company’s lien on the property. Such factors are dependent upon various economic conditions and individual circumstances beyond the Company’s control; the Company is, therefore, subject to risk of loss. The Company believes its lending policies and procedures adequately minimize the potential exposure to such risks and adequate provisions for loan losses are provided for all probable and estimable losses. Collateral and/or government or private guarantees are required for virtually all loans. The Company also holds in its loan portfolio interest-only one-to four-family mortgage loans in which the borrower makes only interest payments for the first five, seven or ten years of the mortgage loan term. This feature will result in future increases in the borrower’s contractually required payments due to the required amortization of the principal amount after the interest-only period. These payment increases could affect the borrower’s ability to repay the loan. The amount of interest-only one-to four-family mortgage loans at December 31, 2015 and December 31, 2014 was $172.3 million , and $288.0 million , respectively. The Company maintained stricter underwriting criteria for these interest-only loans than it did for its amortizing loans. The Company believes these criteria adequately control the potential exposure to such risks and that adequate provisions for loan losses are provided for all known and inherent risks. In the normal course of business the Company sells residential mortgage loans to third parties. These loan sales are subject to customary representations and warranties. In the event that the Company is found to be in breach of these representations and warranties, it may be obligated to repurchase certain of these loans. In connection with its mortgage banking activities, the Company has certain freestanding derivative instruments. At December 31, 2015 , the Company had commitments of approximately $26.5 million to fund loans which will be classified as held-for-sale with a like amount of commitments to sell such loans which are considered derivative instruments under ASC 815, “Derivatives and Hedging.” The Company also had commitments of $19.0 million to sell loans at December 31, 2015 . The fair values of these derivative instruments are immaterial to the Company’s financial condition and results of operations. Standby letters of credit are conditional commitments issued by the Company to guarantee the performance of a customer to a third party. The guarantees generally extend for a term of up to one year and are fully collateralized. For each guarantee issued, if the customer defaults on a payment or performance to the third party, the Company would have to perform under the guarantee. Outstanding standby letters of credit totaled $23.7 million at December 31, 2015 . The fair values of these obligations were immaterial at December 31, 2015 . In addition, at December 31, 2015 , the Company had $617,000 in commercial letters of credit outstanding.

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2015
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements We use fair value measurements to record fair value adjustments to certain assets and liabilities and to determine fair value disclosures. Our securities available-for-sale are recorded at fair value on a recurring basis. Additionally, from time to time, we may be required to record at fair value other assets or liabilities on a non-recurring basis, such as held-to-maturity securities, mortgage servicing rights (“MSR”), loans receivable and real estate owned (“REO”). These non-recurring fair value adjustments involve the application of lower-of-cost-or-market accounting or write-downs of individual assets. Additionally, in connection with our mortgage banking activities we have commitments to fund loans held-for-sale and commitments to sell loans, which are considered free-standing derivative instruments, the fair values of which are not material to our financial condition or results of operations. In accordance with Financial Accounting Standards Board (“FASB”) ASC 820, “ Fair Value Measurements and Disclosures ”, we group our assets and liabilities at fair value in three levels, based on the markets in which the assets are traded and the reliability of the assumptions used to determine fair value. These levels are: • Level 1 – Valuation is based upon quoted prices for identical instruments traded in active markets. • Level 2 – Valuation is based upon quoted prices for similar instruments in active markets, quoted prices for identical or similar instruments in markets that are not active and model-based valuation techniques for which all significant assumptions are observable in the market. • Level 3 – Valuation is generated from model-based techniques that use significant assumptions not observable in the market. These unobservable assumptions reflect our own estimates of assumptions that market participants would use in pricing the asset or liability. Valuation techniques include the use of option pricing models, discounted cash flow models and similar techniques. The results cannot be determined with precision and may not be realized in an actual sale or immediate settlement of the asset or liability. We base our fair values on the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. ASC 820 requires us to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. Assets Measured at Fair Value on a Recurring Basis Securities available-for-sale Our available-for-sale portfolio is carried at estimated fair value on a recurring basis, with any unrealized gains and losses, net of taxes, reported as accumulated other comprehensive income/loss in stockholders’ equity. The fair values of available-for-sale securities are based on quoted market prices (Level 1), where available. The Company obtains one price for each security primarily from a third-party pricing service (pricing service), which generally uses quoted or other observable inputs for the determination of fair value. The pricing service normally derives the security prices through recently reported trades for identical or similar securities, making adjustments through the reporting date based upon available observable market information. For securities not actively traded (Level 2), the pricing service may use quoted market prices of comparable instruments or discounted cash flow analyses, incorporating inputs that are currently observable in the markets for similar securities. Inputs that are often used in the valuation methodologies include, but are not limited to, benchmark yields, credit spreads, default rates, prepayment speeds and non-binding broker quotes. As the Company is responsible for the determination of fair value, it performs quarterly analyses on the prices received from the pricing service to determine whether the prices are reasonable estimates of fair value. Specifically, the Company compares the prices received from the pricing service to a secondary pricing source. Additionally, the Company compares changes in the reported market values and returns to relevant market indices to test the reasonableness of the reported prices. The Company’s internal price verification procedures and review of fair value methodology documentation provided by independent pricing services has not historically resulted in adjustment in the prices obtained from the pricing service. The following tables provide the level of valuation assumptions used to determine the carrying value of our assets measured at fair value on a recurring basis at December 31, 2015 and December 31, 2014 . Carrying Value at December 31, 2015 Total Level 1 Level 2 Level 3 (In thousands) Securities available for sale: Equity securities $ 6,495 6,495 — — Mortgage-backed securities: Federal Home Loan Mortgage Corporation 547,451 — 547,451 — Federal National Mortgage Association 726,072 — 726,072 — Government National Mortgage Association 24,679 — 24,679 — Total mortgage-backed securities available-for-sale 1,298,202 — 1,298,202 — Total securities available-for-sale $ 1,304,697 6,495 1,298,202 — Carrying Value at December 31, 2014 Total Level 1 Level 2 Level 3 (In thousands) Securities available for sale: Equity securities $ 8,523 6,082 2,441 — Mortgage-backed securities: Federal Home Loan Mortgage Corporation 507,283 — 507,283 — Federal National Mortgage Association 681,992 — 681,992 — Government National Mortgage Association 126 — 126 — Total mortgage-backed securities available-for-sale 1,189,401 — 1,189,401 — Total securities available-for-sale $ 1,197,924 6,082 1,191,842 — There have been no changes in the methodologies used at December 31, 2015 from December 31, 2014 , and there were no transfers between Level 1 and Level 2 during the year ended December 31, 2015 . The changes in Level 3 assets measured at fair value on a recurring basis for the years ended December 31, 2015 and 2014 are summarized below: Years Ended December 31, 2015 2014 (Dollars in thousands) Balance beginning of period (1) $ — 670 Total net (losses) gains for the period included in: Net income — 470 Other comprehensive income (loss) — (229 ) Sales — (911 ) Settlements — — Balance end of period $ — — (1) Represents a trust preferred security transferred to available for sale at its fair value on December 31, 2013 due to the impact of the Volcker Rule adopted in December 2013. The Volcker Rule requires specific treatment of certain collateralized debt obligation backed by trust preferred securities. The security was subsequently sold during the twelve months ended December 31, 2014. Assets Measured at Fair Value on a Non-Recurring Basis Mortgage Servicing Rights, net Mortgage servicing rights are carried at the lower of cost or estimated fair value. The estimated fair value of MSR is obtained through independent third party valuations through an analysis of future cash flows, incorporating estimates of assumptions market participants would use in determining fair value including market discount rates, prepayment speeds, servicing income, servicing costs, default rates and other market driven data, including the market’s perception of future interest rate movements. The prepayment speed and the discount rate are considered two of the most significant inputs in the model. At December 31, 2015 , the fair value model used prepayment speeds ranging from 6.30% to 26.28% and a discount rate of 10.20% for the valuation of the mortgage servicing rights. A significant degree of judgment is involved in valuing the mortgage servicing rights using Level 3 inputs. The use of different assumptions could have a significant positive or negative effect on the fair value estimate. Loans Receivable Loans which meet certain criteria are evaluated individually for impairment. A loan is deemed to be impaired if it is a commercial loan with an outstanding balance greater than $1.0 million and on non-accrual status, loans modified in a troubled debt restructuring, and other commercial loans with $1.0 million in outstanding principal if management has specific information that it is probable they will not collect all amounts due under the contractual terms of the loan agreement. Our impaired loans are generally collateral dependent and, as such, are carried at the estimated fair value of the collateral less estimated selling costs. In order to estimate fair value, once interest or principal payments are 90 days delinquent or when the timely collection of such income is considered doubtful an updated appraisal is obtained. Thereafter, in the event the most recent appraisal does not reflect the current market conditions due to the passage of time and other factors, management will obtain an updated appraisal or make downward adjustments to the existing appraised value based on their knowledge of the property, local real estate market conditions, recent real estate transactions, and for estimated selling costs, if applicable. At December 31, 2015 , appraisals were discounted in a range of 0% - 25% . Other Real Estate Owned Other Real Estate Owned is recorded at estimated fair value, less estimated selling costs when acquired, thus establishing a new cost basis. Fair value is generally based on independent appraisals. These appraisals include adjustments to comparable assets based on the appraisers’ market knowledge and experience, and are discounted an additional 0% - 25% for estimated costs to sell. When an asset is acquired, the excess of the loan balance over fair value, less estimated selling costs, is charged to the allowance for loan losses. If the estimated fair value of the asset declines, a writedown is recorded through expense. The valuation of foreclosed assets is subjective in nature and may be adjusted in the future because of changes in economic conditions. Operating costs after acquisition are generally expensed. The following tables provides the level of valuation assumptions used to determine the carrying value of our assets measured at fair value on a non-recurring basis at December 31, 2015 and December 31, 2014 . For the year ended December 31, 2015, there was no change to carrying value of MSR and impaired loans measured at fair value on a non-recurring basis. Security Type Valuation Technique Unobservable Input Range Weighted Average Carrying Value at December 31, 2015 Total Level 1 Level 2 Level 3 (In thousands) Other real estate owned Market comparable Lack of marketability 0.0% - 25.0% 8.90% $ 510 — — 510 $ 510 — — 510 Security Type Valuation Technique Unobservable Input Range Weighted Average Carrying Value at December 31, 2014 Total Level 1 Level 2 Level 3 (In thousands) MSR, net Estimated cash flow Prepayment speeds 5.70% - 29.40% 11.22% $ 13,081 — — 13,081 Other real estate owned Market comparable Lack of marketability 0.0% - 25.0% 15.87% 566 — — 566 $ 13,647 — — 13,647 Other Fair Value Disclosures Fair value estimates, methods and assumptions for the Company’s financial instruments not recorded at fair value on a recurring or non-recurring basis are set forth below. Cash and Cash Equivalents For cash and due from banks, the carrying amount approximates fair value. Securities held-to-maturity Our held-to-maturity portfolio, consisting primarily of mortgage backed securities and other debt securities for which we have a positive intent and ability to hold to maturity, is carried at amortized cost. Management utilizes various inputs to determine the fair value of the portfolio. The Company obtains one price for each security primarily from a third-party pricing service, which generally uses quoted or other observable inputs for the determination of fair value. The pricing service normally derives the security prices through recently reported trades for identical or similar securities, making adjustments through the reporting date based upon available observable market information. For securities not actively traded, the pricing service may use quoted market prices of comparable instruments or discounted cash flow analyses, incorporating inputs that are currently observable in the markets for similar securities. Inputs that are often used in the valuation methodologies include, but are not limited to, benchmark yields, credit spreads, default rates, prepayment speeds and non-binding broker quotes. In the absence of quoted prices and in an illiquid market, valuation techniques, which require inputs that are both significant to the fair value measurement and unobservable, are used to determine fair value of the investment. Valuation techniques are based on various assumptions, including, but not limited to cash flows, discount rates, rate of return, adjustments for nonperformance and liquidity, and liquidation values. As the Company is responsible for the determination of fair value, it performs quarterly analyses on the prices received from the pricing service to determine whether the prices are reasonable estimates of fair value. Specifically, the Company compares the prices received from the pricing service to a secondary pricing source. Additionally, the Company compares changes in the reported market values and returns to relevant market indices to test the reasonableness of the reported prices. The Company’s internal price verification procedures and review of fair value methodology documentation provided by independent pricing services has not historically resulted in adjustment in the prices obtained from the pricing service. FHLB Stock The fair value of FHLB stock is its carrying value, since this is the amount for which it could be redeemed. There is no active market for this stock and the Bank is required to hold a minimum investment based upon the unpaid principal of home mortgage loans and/or FHLB advances outstanding. Loans held for sale The fair value of loans held for sale is its carrying value, since this is the amount for which the Company intends to sell it for. The fair value is determined based on quoted prices for similar instruments in active markets. Loans Fair values are estimated for portfolios of loans with similar financial characteristics. Loans are segregated by type such as residential mortgage and consumer. Each loan category is further segmented into fixed and adjustable rate interest terms and by performing and non-performing categories. The fair value of performing loans, except residential mortgage loans, is calculated by discounting scheduled cash flows through the estimated maturity using estimated market discount rates that reflect the credit and interest rate risk inherent in the loan. For performing residential mortgage loans, fair value is estimated by discounting contractual cash flows adjusted for prepayment estimates using discount rates based on secondary market sources adjusted to reflect differences in servicing and credit costs, if applicable. Fair value for significant non-performing loans is based on recent external appraisals of collateral securing such loans, adjusted for the timing of anticipated cash flows. Fair values estimated in this manner do not fully incorporate an exit price approach to fair value, but instead are based on a comparison to current market rates for comparable loans. Deposit Liabilities The fair value of deposits with no stated maturity, such as savings, checking accounts and money market accounts, is equal to the amount payable on demand. The fair value of certificates of deposit is based on the discounted value of contractual cash flows. The discount rate is estimated using the rates which approximate currently offered for deposits of similar remaining maturities. Borrowings The fair value of borrowings are based on securities dealers’ estimated fair values, when available, or estimated using discounted contractual cash flows using rates which approximate the rates offered for borrowings of similar remaining maturities. Commitments to Extend Credit The fair value of commitments to extend credit is estimated using the fees currently charged to enter into similar agreements, taking into account the remaining terms of the agreements and the present creditworthiness of the counterparties. For commitments to originate fixed rate loans, fair value also considers the difference between current levels of interest rates and the committed rates. Due to the short-term nature of our outstanding commitments, the fair values of these commitments are immaterial to our financial condition. The carrying values and estimated fair values of the Company’s financial instruments are presented in the following table. December 31, 2015 Carrying Estimated Fair Value value Total Level 1 Level 2 Level 3 (In thousands) Financial assets: Cash and cash equivalents $ 148,904 148,904 148,904 — — Securities available-for-sale 1,304,697 1,304,697 6,495 1,298,202 — Securities held-to-maturity 1,844,223 1,888,686 — 1,810,869 77,817 Stock in FHLB 178,437 178,437 178,437 — — Loans held for sale 7,431 7,431 — 7,431 — Net loans 16,661,133 16,650,529 — — 16,650,529 Financial liabilities: Deposits, other than time deposits $ 10,647,346 10,647,346 10,647,346 — — Time deposits 3,416,310 3,414,528 — 3,414,528 — Borrowed funds 3,263,090 3,277,983 — 3,277,983 — December 31, 2014 Carrying Estimated Fair Value value Total Level 1 Level 2 Level 3 (In thousands) Financial assets: Cash and cash equivalents $ 230,961 230,961 230,961 — — Securities available-for-sale 1,197,924 1,197,924 6,082 1,191,842 — Securities held-to-maturity 1,564,479 1,609,365 — 1,544,129 65,236 Stock in FHLB 151,287 151,287 151,287 — — Loans held for sale 6,868 6,868 — 6,868 — Net loans 14,887,570 14,747,319 — — 14,747,319 Financial liabilities: Deposits, other than time deposits $ 9,601,988 9,601,988 9,601,988 — — Time deposits 2,570,338 2,580,572 — 2,580,572 — Borrowed funds 2,766,104 2,796,969 — 2,796,969 — Limitations Fair value estimates are made at a specific point in time, based on relevant market information and information about the financial instrument. These estimates do not reflect any premium or discount that could result from offering for sale at one time the Company’s entire holdings of a particular financial instrument. Because no market exists for a significant portion of the Company’s financial instruments, fair value estimates are based on judgments regarding future expected loss experience, current economic conditions, risk characteristics of various financial instruments, and other factors. These estimates are subjective in nature and involve uncertainties and matters of significant judgment and therefore cannot be determined with precision. Changes in assumptions could significantly affect the estimates. Fair value estimates are based on existing on- and off-balance-sheet financial instruments without attempting to estimate the value of anticipated future business and the value of assets and liabilities that are not considered financial instruments. Significant assets that are not considered financial assets include deferred tax assets, premises and equipment and bank owned life insurance. Liabilities for pension and other postretirement benefits are not considered financial liabilities. In addition, the tax ramifications related to the realization of the unrealized gains and losses can have a significant effect on fair value estimates and have not been considered in the estimates.

Regulatory Capital

Regulatory Capital	12 Months Ended
	Dec. 31, 2015
Regulatory Capital Requirements [Abstract]
Regulatory Capital	Regulatory Capital The Bank and the Company are subject to various regulatory capital requirements administered by the federal banking agencies. Failure to meet minimum capital requirements can initiate certain mandatory and possibly additional discretionary actions by regulators that, if undertaken, could have a direct material effect on the Company’s consolidated financial statements. Under capital adequacy guidelines and the regulatory framework for prompt corrective action, the Bank and the Company must meet specific capital guidelines that involve quantitative measures of assets, liabilities and certain off-balance-sheet items as calculated under regulatory accounting practices. Capital amounts and classification are also subject to qualitative judgments by the regulators about components, risk weightings, and other factors. Quantitative measures established by regulation to ensure capital adequacy require the Bank and the Company to maintain minimum amounts and ratios of Tier 1 leverage ratio, Common equity tier 1 risk-based, Tier 1 risk-based capital and Total risk-based capital (as defined in the regulations). In July 2013, the Federal Deposit insurance Corporation and the other federal bank regulatory agencies issued a final rule that revised their leverage and risk-based capital requirements and the method for calculating riskweighted assets to make them consistent with agreements that were reached by the Basel Committee on Banking Supervision and certain provisions of the Dodd-Frank Act. The Final Capital Rules also revised the quantity and quality of required minimum risk-based and leverage capital requirements, consistent with the Reform Act and the Third Basel Accord adopted by the Basel Committee on Banking Supervision, or Basel III capital standards. The Common equity tier 1 risk-based ratio and changes to the calculation of risk-weighted assets became effective for the Bank and Company on January 1, 2015. As of December 31, 2015 , the most recent notification from the Federal Deposit Insurance Corporation categorized the Bank as well capitalized under the regulatory framework for prompt corrective action. To be categorized as well capitalized, the Bank and the Company must maintain minimum Tier 1 leverage ratio, Common equity tier 1 risk-based, Tier 1 risk-based capital and Total risk-based capital as set forth in the tables. There are no conditions or events since that notification that management believes have changed the Bank and the Company's category. The following is a summary of the Bank and the Company’s actual capital amounts and ratios as of December 31, 2015 compared to the FDIC minimum capital adequacy requirements and the FDIC requirements for classification as a well-capitalized institution. The information presented as of December 31, 2014 reflect the requirements in effect at that time, as the Basel III requirements became effective on January 1, 2015. Actual Minimum Capital Requirement To be Well Capitalized Under Prompt Corrective Action Provisions (1) Amount Ratio Amount Ratio Amount Ratio (Dollars in thousands) As of December 31, 2015: Bank: Tier 1 Leverage Ratio $ 2,558,334 12.41 % $ 824,607 4.00 % $ 1,030,759 5.00 % Common equity tier 1 risk-based 2,558,334 15.87 % 725,523 4.50 % 1,047,978 6.50 % Tier 1 Risk-Based Capital 2,558,334 15.87 % 967,364 6.00 % 1,289,819 8.00 % Total Risk-Based Capital 2,760,081 17.12 % 1,289,819 8.00 % 1,612,274 10.00 % Investors Bancorp, Inc: Tier 1 Leverage Ratio $ 3,259,928 15.80 % $ 825,139 4.00 % n/a n/a Common equity tier 1 risk-based 3,259,928 20.20 % 726,146 4.50 % n/a n/a Tier 1 Risk-Based Capital 3,259,928 20.20 % 968,194 6.00 % n/a n/a Total Risk-Based Capital 3,461,649 21.45 % 1,290,926 8.00 % n/a n/a Actual For Capital Adequacy Purposes To be Well Capitalized Under Prompt Corrective Action Provisions (1) Amount Ratio Amount Ratio Amount Ratio (Dollars in thousands) As of December 31, 2014: Bank: Tier 1 Leverage Ratio $ 2,339,572 12.79 % $ 731,884 4.00 % $ 914,855 5.00 % Tier 1 Risk-Based Capital 2,339,572 17.01 % 550,321 4.00 % 825,481 6.00 % Total Risk-Based Capital 2,511,897 18.26 % 1,100,641 8.00 % 1,375,802 10.00 % Investors Bancorp, Inc: Tier 1 Leverage Ratio $ 3,511,433 19.17 % $ 732,710 4.00 % n/a n/a Tier 1 Risk-Based Capital 3,511,433 25.48 % 551,181 4.00 % n/a n/a Total Risk-Based Capital 3,684,024 26.74 % 1,102,362 8.00 % n/a n/a (1) Prompt corrective action provisions do not apply to the Bank holding company.

Parent Company Only Financial S

Parent Company Only Financial Statements	12 Months Ended
	Dec. 31, 2015
Condensed Financial Information of Parent Company Only Disclosure [Abstract]
Parent Company Only Financial Statements	Parent Company Only Financial Statements The following condensed financial statements for Investors Bancorp, Inc. (parent company only) reflect the investment in its wholly-owned subsidiary, Investors Bank, using the equity method of accounting. Balance Sheets December 31, 2015 2014 (In thousands) Assets: Cash and due from bank $ 569,513 1,022,231 Securities available-for-sale, at estimated fair value 1,733 3,791 Investment in subsidiary 2,611,080 2,409,557 ESOP loan receivable 94,889 96,951 Other assets 45,898 52,499 Total Assets $ 3,323,113 3,585,029 Liabilities and Stockholders’ Equity: Total liabilities $ 11,466 7,174 Total stockholders’ equity 3,311,647 3,577,855 Total Liabilities and Stockholders’ Equity $ 3,323,113 3,585,029 Statements of Operations Year Ended December 31, 2015 2014 2013 (In thousands) Income: Interest on ESOP loan receivable $ 3,151 2,499 1,125 Dividend from subsidiary — — 10,000 Interest on deposit with subsidiary 2 2 2 Interest and dividends on investments 65 64 49 Gain on securities transactions 1,682 145 89 4,900 2,710 11,265 Expenses: Interest expense 54 43 53 Other expenses 3,170 12,197 1,420 Income (loss) before income tax expense 1,676 (9,530 ) 9,792 Income tax (benefit) expense 540 (3,675 ) 233 Income (loss) before undistributed earnings of subsidiary 1,136 (5,855 ) 9,559 Equity in undistributed earnings of subsidiary 180,370 137,576 102,472 Net income $ 181,506 131,721 112,031 Other Comprehensive Income Year Ended December 31, 2015 2014 2013 (In thousands) Net income $ 181,506 131,721 112,031 Other comprehensive income, net of tax: Unrealized gain on securities available-for-sale 433 1,482 1,316 Total other comprehensive income 433 1,482 1,316 Total comprehensive income $ 181,939 133,203 113,347 Statements of Cash Flows Year Ended December 31, 2015 2014 2013 (In thousands) Cash flows from operating activities: Net income $ 181,506 131,721 112,031 Adjustments to reconcile net income to net cash provided by operating activities: (Equity in undistributed earnings of subsidiary) (180,370 ) (137,576 ) (102,472 ) Contribution in stock to charitable foundation — 10,000 — Gain on securities transactions 1,682 145 89 Decrease in other assets 2,107 2,227 2,235 Increase in other liabilities 4,927 525 1,834 Net cash provided by operating activities 9,852 7,042 13,717 Cash flows from investing activities: Capital contributed to the Bank — (1,074,947 ) — Cash received net of cash paid for acquisition — 48 738 Purchase of investments available-for-sale — (493 ) (668 ) Redemption of equity securities available-for-sale 2,700 467 280 Principal collected on ESOP loan 2,062 3,093 1,101 Cash received from MHC merger — 11,307 — Net cash provided by (used in) investing activities 4,762 (1,060,525 ) 1,451 Cash flows from financing activities: Loan to ESOP — (66,553 ) — Proceeds from issuance of common stock — 2,149,893 — Proceeds from sale of treasury stock — 38,227 6,916 Purchase of treasury stock (382,922 ) (13,523 ) (1,531 ) Net tax benefit on stock awards 2,985 3,710 1,262 Dividends paid (87,395 ) (42,555 ) (22,404 ) Net cash (used in) provided by financing activities (467,332 ) 2,069,199 (15,757 ) Net (decrease) increase in cash and due from bank (452,718 ) 1,015,716 (589 ) Cash and due from bank at beginning of year 1,022,231 6,515 7,104 Cash and due from bank at end of year $ 569,513 1,022,231 6,515

Selected Quarterly Financial Da

Selected Quarterly Financial Data	12 Months Ended
	Dec. 31, 2015
Quarterly Financial Information Disclosure [Abstract]
Selected Quarterly Financial Data	Selected Quarterly Financial Data (Unaudited) The following tables are a summary of certain quarterly financial data for the years ended December 31, 2015 and 2014 . 2015 Quarter Ended March 31 June 30 September 30 December 31 (In thousands, except per share data) Interest and dividend income $ 175,159 181,529 186,897 188,138 Interest expense 30,717 32,977 35,623 37,322 Net interest income 144,442 148,552 151,274 150,816 Provision for loan losses 9,000 7,000 5,000 5,000 Net interest income after provision for loan losses 135,442 141,552 146,274 145,816 Non-interest income 8,534 11,585 11,306 8,700 Non-interest expenses 76,909 79,836 85,921 85,666 Income before income tax expense 67,067 73,301 71,659 68,850 Income tax expense 25,120 26,939 22,865 24,448 Net income $ 41,947 46,362 48,794 44,402 Basic and diluted earnings per common share $ 0.12 0.14 0.15 0.14 2014 Quarter Ended March 31 June 30 September 30 December 31 (In thousands, except per share data) Interest and dividend income $ 158,625 164,089 167,058 171,090 Interest expense 29,434 29,326 29,212 30,919 Net interest income 129,191 134,763 137,846 140,171 Provision for loan losses 9,000 8,000 9,000 11,500 Net interest income after provision for loan losses 120,191 126,763 128,846 128,671 Non-interest income 11,942 10,173 9,872 9,874 Non-interest expenses 77,198 112,155 76,584 73,923 Income before income tax expense 54,935 24,781 62,134 64,622 Income tax expense 20,516 9,596 23,092 21,547 Net income $ 34,419 15,185 39,042 43,075 Basic earnings per common share $ 0.10 0.04 0.11 0.13 Diluted earnings per common share 0.10 0.04 0.11 0.12

Earnings Per Share

Earnings Per Share	12 Months Ended
	Dec. 31, 2015
Earnings Per Share [Abstract]
Earnings Per Share	Earnings Per Share The following is a summary of our earnings per share calculations and reconciliation of basic to diluted earnings per share. For the Year Ended December 31, 2015 2014 2013 Income Shares Per Share Amount Income Shares Per Share Amount Income Shares Per Share Amount (Dollars in thousands, except per share data) Net Income $ 181,505 $ 131,721 $ 112,031 Basic earnings per share: Income available to common stockholders $ 181,505 329,763,527 $ 0.55 $ 131,721 344,389,259 $ 0.38 $ 112,031 279,632,558 $ 0.40 Effect of dilutive common stock equivalents (1) 3,169,921 3,342,312 3,403,286 Diluted earnings per share: Income available to common stockholders $ 181,505 332,933,448 $ 0.55 $ 131,721 347,731,571 $ 0.38 $ 112,031 283,035,844 $ 0.40 (1) For the years ended December 31, 2015 , 2014 and 2013 , there were 18,200,877 , 142,953 , and 1,937,015 equity awards, respectively, that could potentially dilute basic earnings per share in the future that were not included in the computation of diluted earnings per share because to do so would have been anti-dilutive for the periods presented.

Comprehensive Income (Loss)

Comprehensive Income (Loss)	12 Months Ended
	Dec. 31, 2015
Equity [Abstract]
Comprehensive Income (Loss)	Comprehensive Income (Loss) The components of comprehensive income (loss), both gross and net of tax, are as follows: Year ended December 31, 2015 Year ended December 31, 2014 Year ended December 31, 2013 Gross Tax Net Gross Tax Net Gross Tax Net (Dollars in thousands) Net income $ 280,877 (99,372 ) 181,505 206,472 (74,751 ) 131,721 175,786 (63,755 ) 112,031 Other comprehensive income (loss): Change in funded status of retirement obligations (2,425 ) 970 (1,455 ) (8,402 ) 3,360 (5,042 ) 16 (6 ) 10 Unrealized (loss) gain on securities available-for-sale (7,982 ) 3,049 (4,933 ) 9,836 (3,884 ) 5,952 (21,930 ) 9,103 (12,827 ) Net Loss on Securities reclassified from available for sale to held to maturity — — — — — — (12,243 ) 5,001 (7,242 ) Accretion of loss on securities reclassified to held to maturity available for sale 2,448 (1,000 ) 1,448 2,918 (1,192 ) 1,726 1,670 (682 ) 988 Unrealized gain on security reclassified from held to maturity to available for sale — — — — — — 233 (95 ) 138 Reclassification adjustment for security (gains) losses included in net income (1,553 ) 6 (1,547 ) (233 ) 95 (138 ) (684 ) 279 (405 ) Noncredit related component other-than-temporary impairment on security — — — — — — 38 (16 ) 22 Other-than-temporary impairment accretion on debt securities 1,802 (736 ) 1,066 1,343 (549 ) 794 2,075 (848 ) 1,227 Total other comprehensive (loss) income (7,710 ) 2,289 (5,421 ) 5,462 (2,170 ) 3,292 (30,825 ) 12,736 (18,089 ) Total comprehensive income $ 273,167 (97,083 ) 176,084 211,934 (76,921 ) 135,013 144,961 (51,019 ) 93,942 The following table presents the after-tax changes in the balances of each component of accumulated other comprehensive loss for the years ended December 31, 2015 and 2014 : Change in funded status of retirement obligations Accretion of loss on securities reclassified to held to maturity Unrealized gain on securities available-for-sale Reclassification adjustment for losses included in net income Other-than- temporary impairment accretion on debt securities Total accumulated other comprehensive loss (Dollars in thousands) Balance - December 31, 2014 $ (10,911 ) (4,528 ) 7,851 — (14,816 ) (22,404 ) Net change (1,455 ) 1,448 (4,933 ) (1,547 ) 1,066 (5,421 ) Balance - December 31, 2015 $ (12,366 ) (3,080 ) 2,918 (1,547 ) (13,750 ) (27,825 ) Balance - December 31, 2013 $ (5,869 ) (6,254 ) 1,899 138 (15,610 ) (25,696 ) Net change (5,042 ) 1,726 5,952 (138 ) 794 3,292 Balance - December 31, 2014 $ (10,911 ) (4,528 ) 7,851 — (14,816 ) (22,404 ) The following table sets for information about amounts reclassified from accumulated other comprehensive loss to the consolidated statement of income and the affected line item in the statement where net income is presented. Year Ended December 31, 2015 2014 (In thousands) Reclassification adjustment for gains included in net income Gain on security transactions $ (1,553 ) (233 ) Change in funded status of retirement obligations (1) Compensation and fringe benefits: Adjustment of net obligation 2,512 (175 ) Amortization of net obligation or asset — 25 Amortization of prior service cost 49 125 Amortization of net gain 1,354 580 Compensation and fringe benefits 3,915 555 Total before tax 2,362 322 Income tax benefit (expense) 976 (205 ) Net of tax $ 1,386 527 (1) These accumulated other comprehensive loss components are included in the computations of net periodic cost for our defined benefit plans and other post-retirement benefit plan. See Note 11 for additional details.

Recent Accounting Pronouncement

Recent Accounting Pronouncements	12 Months Ended
	Dec. 31, 2015
Accounting Changes and Error Corrections [Abstract]
Recent Accounting Pronouncements	Recent Accounting Pronouncements In February 2016, the FASB issued ASU 2016-02, "Leases (Topic 842)," which requires all lessees to recognize a lease liability and a right-of-use asset, measured at the present value of the future minimum lease payments, at the lease commencement date. Lessor accounting remains largely unchanged under the new guidance. The guidance is effective for fiscal years beginning after December 15, 2018, including interim reporting periods within that reporting period, with early adoption permitted. A modified retrospective approach must be applied for leases existing at, or entered into after, the beginning of the earliest comparative period presented in the financial statements. The Company is currently assessing the impact that the guidance will have on the its financial condition and results of operations. In January 2016, the FASB issued ASU 2016-01, “ Financial Instruments- Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities .” This amendment supersedes the guidance to classify equity securities with readily determinable fair values into different categories, requires equity securities to be measured at fair value with changes in the fair value recognized through net income, and simplifies the impairment assessment of equity investments without readily determinable fair values. The amendment requires public business entities that are required to disclose the fair value of financial instruments measured at amortized cost on the balance sheet to measure that fair value using the exit price notion. The amendment requires an entity to present separately in other comprehensive income the portion of the total change in the fair value of a liability resulting from a change in the instrument-specific credit risk when the entity has elected to measure the liability at fair value in accordance with the fair value option. The amendment requires separate presentation of financial assets and financial liabilities by measurement category and form of financial asset on the balance sheet or in the accompanying notes to the financial statements. The amendment reduces diversity in current practice by clarifying that an entity should evaluate the need for a valuation allowance on a deferred tax asset related to available for sale securities in combination with the entity’s other deferred tax assets. This amendment is effective for fiscal years beginning after December 15, 2017, including interim periods within those fiscal years. Entities should apply the amendment by means of a cumulative-effect adjustment as of the beginning of the fiscal year of adoption, with the exception of the amendment related to equity securities without readily determinable fair values, which should be applied prospectively to equity investments that exist as of the date of adoption. The Company intends to adopt the accounting standard during the first quarter of 2018, as required, and is currently evaluating the impact on its results of operations, financial position, and liquidity. In September 2015, the FASB issued ASU 2015-16, “Business Combinations- Simplifying the Accounting for Measurement-Period Adjustments." Under the new rules, acquirers no longer have to retrospectively adjust provisional amounts included in acquisition-date financial statements, when final facts and circumstances are not known on the acquisition date, and later become known in the measurement period. Instead, adjustments that are made in a later period are to be reported in that period. However, acquirers must disclose the amount of adjustments to current period income relating to amounts that would have been recognized in previous periods if the adjustments were recognized as of the acquisition date. For public business entities, the guidance in the ASU is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2015. The Company does not anticipate a material impact to the consolidated financial statements related to this guidance. In April 2015, the FASB issued ASU 2015-03, “Simplifying the Presentation of Debt Issuance Costs.” The ASU changes the presentation of debt issuance costs in financial statements. Under the ASU, an entity presents such costs in the balance sheet as a direct deduction from the related debt liability rather than as an asset. Amortization of the costs is reported as interest expense. According to the ASU’s Basis for Conclusions, debt issuance costs incurred before the associated funding is received should be reported on the balance sheet as deferred charges until that debt liability amount is recorded. For public business entities, the guidance in the ASU is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2015. The Company does not anticipate a material impact to the consolidated financial statements related to this guidance. In April 2015, the FASB issued ASU 2015-04, "Practical Expedient for the Measurement Date of an Employer's Defined Benefit Obligation and Plan Assets." The ASU gives an employer whose fiscal year-end does not coincide with a calendar month-end the ability, as a practical expedient, to measure defined benefit retirement obligations and related plan assets as of the month-end that is closest to its fiscal year-end. The ASU also provides guidance on accounting for contributions to the plan and significant events that require a remeasurement that occur during the period between a month-end measurement date and the employer’s fiscal year-end. An entity should reflect the effects of those contributions or significant events in the measurement of the retirement benefit obligations and related plan assets. The ASU is effective for public business entities for financial statements issued for fiscal years beginning after December 15, 2015, and interim periods within those fiscal years. The Company does not anticipate a material impact to the consolidated financial statements related to this guidance. In May 2014, the FASB issued ASU 2014-09, " Revenue from Contracts with Customers. " The objective of this amendment is to clarify the principles for recognizing revenue and to develop a common revenue standard for U.S. GAAP and IFRS. This update affects any entity that either enters into contracts with customers to transfer goods or services or enters into contracts for the transfer of nonfinancial assets unless those contracts are in the scope of other standards. In April 2015, the FASB issued a proposed ASU to defer for one year the effective date of the new revenue standard. The requirements are effective for annual periods and interim periods within fiscal years beginning after December 15, 2017. The Company does not anticipate a material impact to the consolidated financial statements related to this guidance.

Subsequent Events

Subsequent Events	12 Months Ended
	Dec. 31, 2015
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events As defined in FASB ASC 855, " Subsequent Events ", subsequent events are events or transactions that occur after the balance sheet date but before financial statements are issued or available to be issued. Financial statements are considered issued when they are widely distributed to stockholders and other financial statement users for general use and reliance in a form and format that complies with GAAP. On January 28, 2016, the Company declared a cash dividend of $0.06 per share. The $0.06 dividend per share was paid to stockholders on February 25, 2016, with a record date of February 10, 2016.

Summary of Significant Accoun29

Summary of Significant Accounting Policies Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2015
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The consolidated financial statements are composed of the accounts of Investors Bancorp, Inc. and its wholly owned subsidiaries, including Investors Bank (Bank). All significant intercompany accounts and transactions have been eliminated in consolidation. Certain reclassifications have been made in the consolidated financial statements to conform with current year classifications. In the opinion of management, all the adjustments (consisting of normal and recurring adjustments) necessary for the fair presentation of the consolidated financial condition and the consolidated results of operations for the periods presented have been included. The results of operations and other data presented for the years ended December 31, 2015 , 2014 and 2013 are not necessarily indicative of the results of operations that may be expected for subsequent years. In January 1997, the Bank completed a Plan of Mutual Holding Company Reorganization, utilizing the multi-tier mutual holding company structure. In a series of steps, the Bank formed a Delaware-chartered stock corporation (Investors Bancorp, Inc.) which owned 100% of the common stock of the Bank and formed a New Jersey-chartered mutual holding company (Investors Bancorp, MHC) which initially owned all of the common stock of Investors Bancorp, Inc. On October 11, 2005 , Investors Bancorp, Inc. completed an initial public stock offering. See Note 2. On May 7, 2014, Investors Bancorp, MHC, Investors Bancorp, Inc. and the Bank completed the Plan of Conversion and Reorganization of the Mutual Holding Company (the “Plan”) in which the Bank reorganized from a two-tier mutual holding company structure to a fully public stock holding company structure. The Company raised net proceeds of $2.15 billion by selling a total of 219,580,695 shares of common stock at $10.00 per share in the second step stock offering and issued 1,000,000 shares of common stock to the Investors Charitable Foundation. Concurrent with the completion of the stock offering, each share of Old Investors Bancorp common stock owned by public stockholders (stockholders other than Investors Bancorp, MHC) was exchanged for 2.55 shares of Company common stock. A total of 137,560,968 shares of Company common stock were issued in the exchange. The conversion was accounted for as a capital raising transaction by entities under common control. The historical financial results of Investors Bancorp, MHC are immaterial to the results of the Company and therefore upon completion of the conversion, the net assets of Investors Bancorp, MHC were merged into the Company and are reflected as an increase to stockholders' equity. In addition, the second step conversion resulted in the accelerated vesting of all outstanding stock awards as of the conversion date. The withholding of shares for payment of taxes with respect to these awards resulted in treasury stock of 1,101,694 shares. As a result of the conversion, all share information has been revised to reflect the 2.55 - to- one exchange ratio. Financial information presented in this Form 10-K is derived in part from the consolidated financial statements of Old Investors Bancorp and subsidiaries. See Note 2. The preparation of financial statements in conformity with GAAP requires us to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the dates of the financial statements and the reported amounts of revenues and expenses during the reporting periods. The estimate of our allowance for loan losses, the valuation of mortgage servicing rights (MSR), the valuation of deferred tax assets, impairment judgments regarding goodwill, and fair value and impairment of securities are particularly critical because they involve a higher degree of complexity and subjectivity and require estimates and assumptions about highly uncertain matters. Actual results may differ from our estimates and assumptions. The current economic environment has increased the degree of uncertainty inherent in these material estimates. Business Investors Bancorp, Inc.’s primary business is holding the common stock of the Bank and a loan to the Investors Bank Employee Stock Ownership Plan. The Bank provides banking services to customers primarily through branch offices in New Jersey and New York. The Bank is subject to competition from other financial institutions and is subject to the regulations of certain federal and state regulatory authorities and undergoes periodic examinations by those regulatory authorities.
Cash Equivalents	Cash Equivalents Cash equivalents consist of cash on hand, amounts due from banks and interest-bearing deposits in other financial institutions. The Company is required by the Federal Reserve System to maintain cash reserves equal to a percentage of certain deposits.
Securities	Securities Securities include securities held-to-maturity and securities available-for-sale. Management determines the appropriate classification of securities at the time of purchase. If management has the positive intent not to sell and the Company would not be required to sell prior to maturity, they are classified as held-to-maturity securities. Such securities are stated at amortized cost, adjusted for unamortized purchase premiums and discounts. Securities in the available-for-sale category are debt and mortgage-backed securities which the Company may sell prior to maturity, and all marketable equity securities. Available-for-sale securities are reported at fair value with any unrealized appreciation or depreciation, net of tax effects, reported as accumulated other comprehensive income/loss in stockholders’ equity. Discounts and premiums on securities are accreted or amortized using the level-yield method over the estimated lives of the securities, including the effect of prepayments. Realized gains and losses are recognized when securities are sold or called using the specific identification method. The Company periodically evaluates the security portfolio for other-than-temporary impairment. Other-than-temporary impairment means the Company believes the security’s impairment is due to factors that could include its inability to pay interest or dividends, its potential for default, and/or other factors. In accordance with the Financial Accounting Standards Board (“FASB”) Accounting Standard Codification (“ASC”) Topic 320, “Investments — Debt and Equity Securities” , when a held to maturity or available for sale debt security is assessed for other-than-temporary impairment, the Company has to first consider (a) whether it intends to sell the security, and (b) whether it is more likely than not that the Company will be required to sell the security prior to recovery of its amortized cost basis. If one of these circumstances applies to a security, an other-than-temporary impairment loss is recognized in the statement of income equal to the full amount of the decline in fair value below amortized cost. If neither of these circumstances applies to a security, but the Company does not expect to recover the entire amortized cost basis, an other-than-temporary impairment loss has occurred that must be separated into two categories: (a) the amount related to credit loss, and (b) the amount related to other factors. In assessing the level of other-than-temporary impairment attributable to credit loss, the Company compares the present value of cash flows expected to be collected with the amortized cost basis of the security. The portion of the total other-than-temporary impairment related to credit loss is recognized in earnings, while the amount related to other factors is recognized in other comprehensive income. The total other-than-temporary impairment loss is presented in the statement of income, less the portion recognized in other comprehensive income. When a debt security becomes other-than-temporarily impaired, its amortized cost basis is reduced to reflect the portion of the total impairment related to credit loss. To determine whether a security’s impairment is other-than-temporary, the Company considers factors that include, the duration and severity of the impairment; the Company’s ability and intent to hold security investments until they recover in value (as well as the likelihood of such a recovery in the near term); the Company’s intent to sell security investments; and whether it is more likely than not that the Company will be required to sell such securities before recovery of their individual amortized cost basis less any current-period credit loss. For debt securities, the primary consideration in determining whether impairment is other-than-temporary is whether or not it is probable that current or future contractual cash flows have been or may be impaired.
Loans Receivable, Net	Loans Receivable, Net Loans receivable, other than loans held-for-sale, are stated at unpaid principal balance, adjusted by unamortized premiums and unearned discounts, net deferred origination fees and costs, net purchase accounting adjustments and the allowance for loan losses. Interest income on loans is accrued and credited to income as earned. Premiums and discounts on purchased loans and net loan origination fees and costs are deferred and amortized to interest income over the estimated life of the loan as an adjustment to yield. The allowance for loan losses is increased by the provision for loan losses charged to earnings and is decreased by charge-offs, net of recoveries. The provision for loan losses is based on management’s evaluation of the adequacy of the allowance which considers, among other things, the Company’s past loan loss experience (using the appropriate look-back and loss emergence periods), known and inherent risks in the portfolio, existing adverse situations that may affect the borrower’s ability to repay, estimated value of any underlying collateral and current economic conditions. While management uses available information to recognize estimated losses on loans, future additions may be necessary based on changes in economic or other conditions. In addition, various regulatory agencies, as an integral part of their examination process, periodically review the Company’s allowance for loan losses. Such agencies may require the Company to recognize additions to the allowance based upon their judgments and information available to them at the time of their examinations. A loan is considered delinquent when we have not received a payment within 30 days of its contractual due date. The accrual of income on loans is discontinued when interest or principal payments are 90 days in arrears or when the timely collection of such income is doubtful. Loans on which the accrual of income has been discontinued are designated as non-accrual loans and outstanding interest previously credited is reversed. Interest income on non-accrual loans and impaired loans is recognized in the period collected unless the ultimate collection of principal is considered doubtful. A loan is returned to accrual status when all amounts due have been received and the remaining principal is deemed collectible. Loans are generally charged off after an analysis is completed which indicates that collectability of the full principal balance is in doubt.
Impaired Loan	The Company defines an impaired loan as a loan for which it is probable, based on current information, that the lender will not collect all amounts due under the contractual terms of the loan agreement. The Company evaluates commercial loans with an outstanding balance greater than $1.0 million and on non-accrual status, loans modified in a troubled debt restructuring (“TDR”), and other loans over $1.0 million outstanding balance if management has specific information that it is probable they will not collect all amounts due under the contractual terms of the loan agreement for impairment. Impaired loans are individually evaluated to determine that the loan’s carrying value is not in excess of the fair value of the collateral or the present value of the expected future cash flows. Smaller balance homogeneous loans are evaluated for impairment collectively unless they are modified in a trouble debt restructure. Such loans include residential mortgage loans, consumer loans, and loans not meeting the Company’s definition of impaired, and are specifically excluded from impaired loans. Purchased Credit-Impaired ("PCI") loans, are loans acquired at a discount that is due, in part, to credit quality. PCI loans are accounted for in accordance with ASC Subtopic 310-30 and are initially recorded at fair value (as determined by the present value of expected future cash flows) with no valuation allowance (i.e., the allowance for loan losses). The difference between the undiscounted cash flows expected at acquisition and the initial carrying amount (fair value) of the PCI loans, or the “accretable yield,” is recognized as interest income utilizing the level-yield method over the life of the loans. Contractually required payments for interest and principal that exceed the undiscounted cash flows expected at acquisition, or the “non-accretable difference,” are not recognized as a yield adjustment, as a loss accrual or a valuation allowance. Reclassifications of the non-accretable difference to the accretable yield may occur subsequent to the loan acquisition dates due to increases in expected cash flows of the loans and result in an increase in yield on a prospective basis.
Loans Held-for-Sale	Loans Held-for-Sale Loans held-for-sale are carried at the lower of cost or estimated fair value, as determined on an aggregate basis. Net unrealized losses, if any, are recognized in a valuation allowance through charges to earnings. Premiums and discounts and origination fees and costs on loans held-for-sale are deferred and recognized as a component of the gain or loss on sale. Gains and losses on sales of loans held-for-sale are recognized on settlement dates and are determined by the difference between the sale proceeds and the carrying value of the loans. These transactions are accounted for as sales based on our satisfaction of the criteria for such accounting which provide that, as transferor, we have surrendered control over the loans.
Federal Home Loan Bank Stock	Stock in the Federal Home Loan Bank The Bank, as a member of the Federal Home Loan Bank of New York (FHLB), is required to hold shares of capital stock of the FHLB based on our activities, primarily our outstanding borrowings, with the FHLB. The stock is carried at cost, less any impairment.
Office Properties and Equipment, Net	Office Properties and Equipment, Net Land is carried at cost. Office buildings, leasehold improvements and furniture, fixtures and equipment are carried at cost, less accumulated depreciation and amortization. Office buildings and furniture, fixtures and equipment are depreciated using an accelerated basis over the estimated useful lives of the respective assets. Leasehold improvements are amortized using the straight-line method over the terms of the respective leases or the lives of the assets, whichever is shorter.
Bank Owned Life Insurance	Bank Owned Life Insurance Bank owned life insurance is carried at the amount that could be realized under the Company’s life insurance contracts as of the date of the consolidated balance sheets and is classified as a non-interest earning asset. Increases in the carrying value are recorded as non-interest income in the consolidated statements of income and insurance proceeds received are generally recorded as a reduction of the carrying value. The carrying value consists of cash surrender value of $152.5 million at December 31, 2015 and $155.8 million at December 31, 2014 and a claims stabilization reserve of $6.6 million at December 31, 2015 and $5.8 million at December 31, 2014 . Repayment of the claims stabilization reserve (funds transferred from the cash surrender value to provide for future death benefit payments) and the deferred acquisition costs (costs incurred by the insurance carrier for the policy issuance) is guaranteed by the insurance carrier provided that certain conditions are met at the date of a contract is surrendered. The Company satisfied these conditions at December 31, 2015 and 2014.
Intangible Assets	Intangible Assets Goodwill. Goodwill is presumed to have an indefinite useful life and is tested, at least annually, for impairment at the reporting unit level. Impairment exists when the carrying amount of goodwill exceeds its implied fair value. For purposes of our goodwill impairment testing, we have identified the Bank as a single reporting unit. At December 31, 2015 , the carrying amount of our goodwill totaled $77.6 million . In connection with our annual impairment assessment we applied the guidance in FASB Accounting Standards Update (“ASU”) 2011-08, Intangibles—Goodwill and Other (Topic 350): Testing Goodwill for Impairment, which permits an entity to make a qualitative assessment of whether it is more likely than not that a reporting unit’s fair value is less than its carrying amount before applying the two-step goodwill impairment test. For the year ended December 31, 2015 , the Company’s qualitative assessment concluded that it was not more likely than not that the fair value of the reporting unit is less than its carrying amount and, therefore, the two-step goodwill impairment test was not required. Mortgage Servicing Rights . The Company recognizes as separate assets the rights to service mortgage loans. The right to service loans for others is generally obtained through the sale of loans with servicing retained. The initial asset recognized for originated mortgage servicing rights (“MSR”) is measured at fair value. The fair value of MSR is estimated by reference to current market values of similar loans sold with servicing released. MSR are amortized in proportion to and over the period of estimated net servicing income. We apply the amortization method for measurements of our MSR. MSR are assessed for impairment based on fair value at each reporting date. MSR impairment, if any, is recognized in a valuation allowance through charges to earnings as a component of fees and service charges. Increases in the fair value of impaired MSR are recognized only up to the amount of the previously recognized valuation allowance. Fees earned for servicing loans are reported as income when the related mortgage loan payments are collected. Core Deposit Premiums . Core deposit premiums represent the intangible value of depositor relationships assumed in purchase acquisitions and are amortized on an accelerated basis over 10 years. The Company periodically evaluates the value of core deposit premiums to ensure the carrying amount exceeds it implied fair value.
Other Real Estate Owned	Other Real Estate Owned Real estate owned (REO) consists of properties acquired through foreclosure or deed in lieu of foreclosure. Such assets are carried at the lower of cost or fair value, less estimated selling costs, based on independent appraisals. Write-downs required at the time of acquisition are charged to the allowance for loan losses. Thereafter, decreases in the properties’ estimated fair value which are charged to income along with any additional property maintenance and protection expenses incurred in owning the property.
Federal Home Loan Bank Borrowings	Our FHLB borrowings, frequently referred to as advances, are over collateralized by our residential and non residential mortgage portfolios as well as qualified investment securities.
Borrowed Funds	The Bank also enters into sales of securities under agreements to repurchase with selected brokers and the FHLB. The securities underlying the agreements are delivered to the counterparty who agrees to resell to the Bank the identical securities at the maturity or call of the agreement. These agreements are recorded as financing transactions, as the Bank maintains effective control over the transferred securities, and no gain or loss is recognized. The dollar amount of the securities underlying the agreements continues to be carried in the Bank’s securities portfolio. The obligations to repurchase the securities are reported as a liability in the consolidated balance sheets.
Income Taxes	Income Taxes The Company records income taxes in accordance with Accounting Standard Codification (ASC) 740 “Income Taxes,” as amended, using the asset and liability method. Accordingly, deferred tax assets and liabilities: (i) are recognized for the expected future tax consequences of events that have been recognized in the financial statements or tax returns; (ii) are attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases; and (iii) are measured using enacted tax rates expected to apply in the years when those temporary differences are expected to be recovered or settled. Where applicable, deferred tax assets are reduced by a valuation allowance for any portions determined not likely to be realized. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income tax expense in the period of enactment. The valuation allowance is adjusted, by a charge or credit to income tax expense, as changes in facts and circumstances warrant. The Company recognizes accrued interest and penalties related to unrecognized tax benefits, where applicable, in income tax expense.
Employee Benefits	Employee Benefits The Company has a defined benefit pension plan which covers all employees who satisfy the eligibility requirements. The Company participates in a multiemployer plan. Costs of the pension plan are based on the contributions required to be made to the plan. The Company has two Supplemental Employee Retirement Plans (SERPs). The SERPs are a nonqualified, defined benefit plans which provide benefits to certain eligible employees of the Company whose benefits and/or contributions under the pension plan are limited by the Internal Revenue Code. The Company also has a nonqualified, defined benefit plan which provides benefits to its directors. The SERP and the directors’ plan are unfunded and the costs of the plans are recognized over the period that services are provided. The Company has a 401(k) plan covering substantially all employees. The Company matches 50% of the first 6% contributed by participants and recognizes expense as its contributions are made.
Share-based Compensation	The employee stock ownership plan (ESOP) is accounted for in accordance with the provisions of Statement ASC 718-40, “Employers’ Accounting for Employee Stock Ownership Plans.” The funds borrowed by the ESOP from the Company to purchase the Company’s common stock are being repaid from the Bank’s contributions over a period of up to 30 years. The Company’s common stock not yet allocated to participants is recorded as a reduction of stockholders’ equity at cost. Compensation expense for the ESOP is based on the market price of the Company’s stock and is recognized as shares are committed to be released to participants due to the repayment of the loan by the ESOP to the Company. The Company recognizes the cost of employee services received in exchange for awards of equity instruments based on the grant-date fair value of those awards in accordance with ASC 718, “Compensation-Stock Compensation”. The Company estimates the per share fair value of option grants on the date of grant using the Black-Scholes option pricing model using assumptions for the expected dividend yield, expected stock price volatility, risk-free interest rate and expected option term. These assumptions are subjective in nature, involve uncertainties and, therefore, cannot be determined with precision. The Black-Scholes option pricing model also contains certain inherent limitations when applied to options that are not traded on public markets. The per share fair value of options is highly sensitive to changes in assumptions. In general, the per share fair value of options will move in the same direction as changes in the expected stock price volatility, risk-free interest rate and expected option term, and in the opposite direction as changes in the expected dividend yield. For example, the per share fair value of options will generally increase as expected stock price volatility increases, risk-free interest rate increases, expected option term increases and expected dividend yield decreases. The use of different assumptions or different option pricing models could result in materially different per share fair values of options.
Earnings Per Share	Earnings Per Share Basic earnings per common share, or EPS, are computed by dividing net income by the weighted-average common shares outstanding during the year. The weighted-average common shares outstanding includes the weighted-average number of shares of common stock outstanding less the weighted average number of unvested shares of restricted stock and unallocated shares held by the ESOP. For EPS calculations, ESOP shares that have been committed to be released are considered outstanding. ESOP shares that have not been committed to be released are excluded from outstanding shares on a weighted average basis for EPS calculations. Diluted EPS is computed using the same method as basic EPS, but includes the effect of all potentially dilutive common shares that were outstanding during the period, such as unexercised stock options and unvested shares of restricted stock, calculated using the treasury stock method. When applying the treasury stock method, we add: (1) the assumed proceeds from option exercises; (2) the tax benefit that would have been credited to additional paid-in capital assuming exercise of non-qualified stock options and vesting of shares of restricted stock; and (3) the average unamortized compensation costs related to unvested shares of restricted stock and stock options. We then divide this sum by our average stock price to calculate shares repurchased. The excess of the number of shares issuable over the number of shares assumed to be repurchased is added to basic weighted average common shares to calculate diluted EPS.

Business Combinations (Tables)

Business Combinations (Tables)	12 Months Ended
	Dec. 31, 2015
Gateway Community Financial Corporation
Business Acquisition [Line Items]
Summary of Estimated Fair Values of the Assets Acquired and Liabilities Assumed	The following table summarizes the estimated fair values of the assets acquired and liabilities assumed at the date of acquisition for Gateway Financial, net of cash consideration paid: At January 10, 2014 (In millions) Cash and cash equivalents, net $ 17.9 Securities available-for-sale 50.3 Loans receivable 195.1 Accrued interest receivable 0.7 Other real estate owned 0.4 Office properties and equipment, net 4.3 Intangible assets 1.9 Other assets 15.9 Total assets acquired 286.5 Deposits (254.7 ) Borrowed funds (5.2 ) Other liabilities (3.1 ) Total liabilities assumed $ (263.0 ) Net assets acquired $ 23.5

Securities (Tables)

Securities (Tables)	12 Months Ended
	Dec. 31, 2015
Investments, Debt and Equity Securities [Abstract]
Summary of securities	The following tables present the carrying value, gross unrealized gains and losses and estimated fair value for available-for-sale securities and the amortized cost, net unrealized losses, gross unrecognized gains and losses and estimated fair value for held-to-maturity securities as of the dates indicated: At December 31, 2015 Carrying value Gross unrealized gains Gross unrealized losses Estimated fair value (In thousands) Available-for-sale: Equity securities $ 5,778 733 16 6,495 Mortgage-backed securities: Federal Home Loan Mortgage Corporation 546,652 3,242 2,443 547,451 Federal National Mortgage Association 724,851 4,520 3,299 726,072 Government National Mortgage Association 24,841 1 163 24,679 Total mortgage-backed securities available-for-sale 1,296,344 7,763 5,905 1,298,202 Total available-for-sale securities $ 1,302,122 8,496 5,921 1,304,697 At December 31, 2015 Amortized cost Net unrealized losses (1) Carrying value Gross unrecognized gains (2) Gross unrecognized losses (2) Estimated fair value (In thousands) Held-to-maturity: Debt securities: Government-sponsored enterprises $ 4,232 — 4,232 11 — 4,243 Municipal bonds 43,058 — 43,058 1,307 — 44,365 Corporate and other debt securities 58,358 (23,245 ) 35,113 42,704 77,817 Total debt securities held-to-maturity 105,648 (23,245 ) 82,403 44,022 — 126,425 Mortgage-backed securities: Federal Home Loan Mortgage Corporation 516,841 (2,502 ) 514,339 2,213 3,082 513,470 Federal National Mortgage Association 1,228,845 (2,705 ) 1,226,140 7,305 6,120 1,227,325 Government National Mortgage Association 21,330 — 21,330 125 — 21,455 Federal Housing Authorities 11 — 11 — — 11 Total mortgage-backed securities held-to-maturity 1,767,027 (5,207 ) 1,761,820 9,643 9,202 1,762,261 Total held-to-maturity securities $ 1,872,675 (28,452 ) 1,844,223 53,665 9,202 1,888,686 At December 31, 2014 Carrying value Gross unrealized gains Gross unrealized losses Estimated fair value (In thousands) Available-for-sale: Equity securities $ 6,887 1,636 — 8,523 Mortgage-backed securities: Federal Home Loan Mortgage Corporation 503,268 5,023 1,008 507,283 Federal National Mortgage Association 675,535 7,641 1,184 681,992 Government National Mortgage Association 125 1 — 126 Total mortgage-backed securities available-for-sale 1,178,928 12,665 2,192 1,189,401 Total available-for-sale securities $ 1,185,815 14,301 2,192 1,197,924 At December 31, 2014 Amortized cost Net unrealized losses (1) Carrying Value Gross unrecognized gains (2) Gross unrecognized losses (2) Estimated fair value (In thousands) Held-to-maturity: Debt securities: Government-sponsored enterprises $ 4,388 — 4,388 15 — 4,403 Municipal bonds 24,320 — 24,320 1,001 — 25,321 Corporate and other debt securities 58,487 (25,047 ) 33,440 32,163 367 65,236 Total debt securities held-to-maturity 87,195 (25,047 ) 62,148 33,179 367 94,960 Mortgage-backed securities: Federal Home Loan Mortgage Corporation 504,407 (3,770 ) 500,637 3,561 1,878 502,320 Federal National Mortgage Association 978,261 (3,885 ) 974,376 11,629 1,218 984,787 Government National Mortgage Association 27,136 — 27,136 — 20 27,116 Federal housing authorities 182 — 182 — — 182 Total mortgage-backed securities held-to-maturity 1,509,986 (7,655 ) 1,502,331 15,190 3,116 1,514,405 Total held-to-maturity securities $ 1,597,181 (32,702 ) 1,564,479 48,369 3,483 1,609,365 (1) Net unrealized losses of held-to-maturity corporate and other debt securities represent the other than temporary charge related to other non-credit factors and is being amortized through accumulated other comprehensive income over the remaining life of the securities. For mortgage-backed securities, it represents the net loss on previously designated available-for sale securities transferred to held-to-maturity at fair value and is being amortized through accumulated other comprehensive income over the remaining life of the securities. (2) Unrecognized gains and losses of held-to-maturity securities are not reflected in the financial statements, as they represent fair value fluctuations from the later of: (i) the date a security is designated as held-to-maturity; or (ii) the date that an OTTI charge is recognized on a held-to-maturity security, through the date of the balance sheet.
Investments Classified by Contractual Maturity Date	The amortized cost and estimated fair value of debt securities at December 31, 2015 , by contractual maturity, are shown below. December 31, 2015 Carrying Value Estimated fair value (In thousands) Due in one year or less $ 40,136 40,136 Due after one year through five years 2,363 2,375 Due after five years through ten years — — Due after ten years 39,904 83,914 Total $ 82,403 126,425
Investment Securities, Continuous Unrealized Loss Position and Fair Value	Gross unrealized losses on securities and the estimated fair value of the related securities, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position at December 31, 2015 and December 31, 2014 , was as follows: December 31, 2015 Less than 12 months 12 months or more Total Estimated fair value Unrealized losses Estimated fair value Unrealized losses Estimated fair value Unrealized losses (In thousands) Available-for-sale: Equity Securities $ 4,692 16 — — 4,692 16 Mortgage-backed securities: Federal Home Loan Mortgage Corporation $ 263,255 2,443 — — 263,255 2,443 Federal National Mortgage Association 375,792 2,850 14,821 449 390,613 3,299 Government National Mortgage Association 24,874 163 24,874 163 Total mortgage-backed securities available-for-sale 663,921 5,456 14,821 449 678,742 5,905 Total available-for-sale securities $ 668,613 5,472 14,821 449 683,434 5,921 Held-to-maturity: Mortgage-backed securities: Federal Home Loan Mortgage Corporation 342,702 2,804 4,887 278 347,589 3,082 Federal National Mortgage Association 547,326 5,477 29,013 643 576,339 6,120 Total mortgage-backed securities held-to-maturity 890,028 8,281 33,900 921 923,928 9,202 Total held-to-maturity securities $ 890,028 8,281 33,900 921 923,928 9,202 Total $ 1,558,641 13,753 48,721 1,370 1,607,362 15,123 December 31, 2014 Less than 12 months 12 months or more Total Estimated fair value Unrealized losses Estimated fair value Unrealized losses Estimated fair value Unrealized losses (In thousands) Available-for-sale: Mortgage-backed securities: Federal Home Loan Mortgage Corporation 76,525 426 60,394 582 136,919 1,008 Federal National Mortgage Association 67,017 50 52,519 1,134 119,536 1,184 Total mortgage-backed securities available-for-sale 143,542 476 112,913 1,716 256,455 2,192 Total available-for-sale securities 143,542 476 112,913 1,716 256,455 2,192 Held-to-maturity: Debt securities: Corporate and other debt securities 674 40 233 327 907 367 Mortgage-backed securities: Federal Home Loan Mortgage Corporation 199,962 1,043 47,892 835 247,854 1,878 Federal National Mortgage Association 145,520 371 37,517 847 183,037 1,218 Government National Mortgage Association 27,116 20 — — 27,116 20 Total mortgage-backed securities held-to-maturity 372,598 1,434 85,409 1,682 458,007 3,116 Total held-to-maturity securities $ 373,272 1,474 85,642 2,009 458,914 3,483 Total $ 516,814 1,950 198,555 3,725 715,369 5,675
Changes in Credit Loss Component of the Impairment Loss of Debt Securities for Other-than-Temporary Impairment Recognized in Earnings	The following table presents the changes in the credit loss component of the impairment loss of debt securities that the Company has written down for such loss as an other-than-temporary impairment recognized in earnings. For the Years Ended December 31, 2015 2014 2013 (In thousands) Balance of credit related OTTI, beginning of period $ 108,817 112,235 114,514 Additions: Initial credit impairments — — — Subsequent credit impairments — — 977 Reductions: Accretion of credit loss impairment due to an increase in expected cash flows (3,804 ) (3,418 ) (3,256 ) Reduction for securities sold or paid off during the period (4,813 ) — — Balance of credit related OTTI, end of period $ 100,200 108,817 112,235

Loans Receivable, Net (Tables)

Loans Receivable, Net (Tables)	12 Months Ended
	Dec. 31, 2015
Receivables [Abstract]
Schedule of Accounts, Notes, Loans and Financing Receivable	The detail of the loan portfolio as of December 31, 2015 and December 31, 2014 was as follows: December 31, December 31, (In thousands) Multi-family loans $ 6,255,904 5,048,477 Commercial real estate loans 3,821,950 3,139,824 Commercial and industrial loans 1,044,329 544,402 Construction loans 224,057 143,664 Total commercial loans 11,346,240 8,876,367 Residential mortgage loans 5,037,898 5,764,896 Consumer and other loans 496,103 440,500 Total loans excluding PCI loans 16,880,241 15,081,763 PCI loans 11,089 17,789 Net unamortized premiums/discounts and deferred loan fees/costs (1) (11,692 ) (11,698 ) Allowance for loan losses (218,505 ) (200,284 ) Net loans $ 16,661,133 14,887,570 (1) Included in unamortized premiums/discounts and deferred loan fees/costs are accretable purchase accounting adjustments in connection with loans acquired.
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period	The following table presents information regarding the estimates of the contractually required payments, the cash flows expected to be collected and the estimated fair value of the PCI loans acquired in the Gateway Financial acquisition as of January 10, 2014: January 10, 2014 (In thousands) Contractually required principal and interest $ 4,172 Contractual cash flows not expected to be collected (non-accretable difference) (1,024 ) Expected cash flows to be collected 3,148 Interest component of expected cash flows (accretable yield) (216 ) Fair value of acquired loans $ 2,932
Schedule of Accretable Yield Movement	The following table presents changes in the accretable yield for PCI loans during the years ended December 31, 2015 and 2014 : Years Ended December 31, 2015 2014 (In thousands) Balance, beginning of period $ 971 4,154 Acquisitions — 216 Accretion (1) (522 ) (3,399 ) Net reclassification from non-accretable difference — — Balance, end of period $ 449 971 (1) Includes the removal of $1.9 million accretable mark on PCI loans sold during the year ended December 31, 2014 . This transfer had no impact on income for the year ended December 31, 2014 .
Summary of Analysis of the Allowance for Loan Losses	An analysis of the allowance for loan losses is summarized as follows: Years Ended December 31, 2015 2014 2013 (In thousands) Balance at beginning of the period $ 200,284 173,928 142,172 Loans charged off (12,216 ) (18,244 ) (22,610 ) Recoveries 4,437 7,100 3,866 Net charge-offs (7,779 ) (11,144 ) (18,744 ) Provision for loan losses 26,000 37,500 50,500 Balance at end of the period $ 218,505 200,284 173,928
Summary of Loan Losses and the Recorded Investment in Loans by Portfolio Segment and Based On Impairment Method	The following tables present the balance in the allowance for loan losses and the recorded investment in loans by portfolio segment and based on impairment method as of the years ended December 31, 2015 and 2014 : December 31, 2015 Multi- Family Loans Commercial Real Estate Loans Commercial and Industrial Loans Construction Loans Residential Mortgage Loans Consumer and Other Loans Unallocated Total (Dollars in thousands) Allowance for loan losses: Beginning balance-December 31, 2014 $ 71,147 44,030 20,759 6,488 47,936 3,347 6,577 200,284 Charge-offs (284 ) (1,021 ) (516 ) (466 ) (9,526 ) (403 ) — (12,216 ) Recoveries 445 807 295 317 2,295 278 — 4,437 Provision 16,915 3,183 20,047 455 (9,262 ) (67 ) (5,271 ) 26,000 Ending balance-December 31, 2015 $ 88,223 46,999 40,585 6,794 31,443 3,155 1,306 218,505 Individually evaluated for impairment $ — — 2,409 — 1,773 9 — 4,191 Collectively evaluated for impairment 88,223 46,999 38,176 6,794 29,670 3,146 1,306 214,314 Loans acquired with deteriorated credit quality — — — — — — — Balance at December 31, 2015 $ 88,223 46,999 40,585 6,794 31,443 3,155 1,306 218,505 Loans: Individually evaluated for impairment $ 3,219 18,941 9,395 2,504 22,539 389 — 56,987 Collectively evaluated for impairment 6,252,685 3,803,009 1,034,934 221,553 5,015,359 495,714 — 16,823,254 Loans acquired with deteriorated credit quality — 7,149 56 1,786 1,645 453 — 11,089 Balance at December 31, 2015 $ 6,255,904 3,829,099 1,044,385 225,843 5,039,543 496,556 — 16,891,330 December 31, 2014 Multi- Family Loans Commercial Real Estate Loans Commercial and Industrial Loans Construction Loans Residential Mortgage Loans Consumer and Other Loans Unallocated Total (Dollars in thousands) Allowance for loan losses: Beginning balance-December 31, 2013 $ 42,103 46,657 9,273 8,947 51,760 2,161 13,027 173,928 Charge-offs (323 ) (6,147 ) (2,447 ) (640 ) (7,715 ) (972 ) — (18,244 ) Recoveries 3,784 201 516 799 1,783 17 — 7,100 Provision 25,583 3,319 13,417 (2,618 ) 2,108 2,141 (6,450 ) 37,500 Ending balance-December 31, 2014 $ 71,147 44,030 20,759 6,488 47,936 3,347 6,577 200,284 Individually evaluated for impairment $ — 274 — — 1,865 — — 2,139 Collectively evaluated for impairment 71,147 43,756 20,759 6,488 46,071 3,347 6,577 198,145 Loans acquired with deteriorated credit quality — — — — — — — — Balance at December 31, 2014 $ 71,147 44,030 20,759 6,488 47,936 3,347 6,577 200,284 Loans: Individually evaluated for impairment $ 4,111 22,995 3,310 6,798 23,285 — — 60,499 Collectively evaluated for impairment 5,044,366 3,116,829 541,092 136,866 5,741,611 440,500 — 15,021,264 Loans acquired with deteriorated credit quality 637 7,329 56 4,732 4,581 454 — 17,789 Balance at December 31, 2014 $ 5,049,114 3,147,153 544,458 148,396 5,769,477 440,954 — 15,099,552
Schedule of Risk Category of Loans by Class of Loans	The following tables present the risk category of loans as of December 31, 2015 and December 31, 2014 by class of loans excluding PCI loans: December 31, 2015 Pass Watch Special Mention Substandard Doubtful Loss Total (In thousands) Commercial loans: Multi-family $ 5,876,425 325,414 17,033 37,032 — — 6,255,904 Commercial real estate 3,411,876 331,429 38,265 40,380 — — 3,821,950 Commercial and industrial 793,527 223,474 13,782 13,546 — — 1,044,329 Construction 207,499 12,833 — 3,725 — — 224,057 Total commercial loans 10,289,327 893,150 69,080 94,683 — — 11,346,240 Residential mortgage 4,930,961 24,584 13,796 68,557 — — 5,037,898 Consumer and other 482,715 3,987 427 8,974 — — 496,103 Total $ 15,703,003 921,721 83,303 172,214 — — 16,880,241 December 31, 2014 Pass Watch Special Mention Substandard Doubtful Loss Total (In thousands) Commercial loans: Multi-family $ 4,710,124 247,921 62,886 27,546 — — 5,048,477 Commercial real estate 2,757,949 276,660 29,248 75,967 — — 3,139,824 Commercial and industrial 405,021 110,374 20,321 8,686 — — 544,402 Construction 134,356 2,228 2,075 5,005 — — 143,664 Total commercial loans 8,007,450 637,183 114,530 117,204 — — 8,876,367 Residential mortgage 5,641,184 22,059 7,657 93,996 — — 5,764,896 Consumer and other 431,314 3,987 1,006 4,193 — — 440,500 Total $ 14,079,948 663,229 123,193 215,393 — — 15,081,763
Payment Status of the Recorded Investment in Past Due Loans	The following tables present the payment status of the recorded investment in past due loans as of December 31, 2015 and December 31, 2014 by class of loans excluding PCI loans: December 31, 2015 30-59 Days 60-89 Days Greater than 90 Days Total Past Due Current Total Loans Receivable (In thousands) Commercial loans: Multi-family $ 14,236 — 1,886 16,122 6,239,782 6,255,904 Commercial real estate 4,171 352 6,429 10,952 3,810,998 3,821,950 Commercial and industrial 957 — 4,386 5,343 1,038,986 1,044,329 Construction — — 792 792 223,265 224,057 Total commercial loans 19,364 352 13,493 33,209 11,313,031 11,346,240 Residential mortgage 27,092 14,956 68,560 110,608 4,927,290 5,037,898 Consumer and other 3,987 427 8,976 13,390 482,713 496,103 Total $ 50,443 15,735 91,029 157,207 16,723,034 16,880,241 December 31, 2014 30-59 Days 60-89 Days Greater than 90 Days Total Past Due Current Total Loans Receivable (In thousands) Commercial loans: Multi-family $ 698 239 2,989 3,926 5,044,551 5,048,477 Commercial real estate 6,566 778 13,940 21,284 3,118,540 3,139,824 Commercial and industrial 792 395 2,903 4,090 540,312 544,402 Construction — — 4,345 4,345 139,319 143,664 Total commercial loans 8,056 1,412 24,177 33,645 8,842,722 8,876,367 Residential mortgage 23,712 8,900 75,610 108,222 5,656,674 5,764,896 Consumer and other 1,334 1,006 4,211 6,551 433,949 440,500 Total $ 33,102 11,318 103,998 148,418 14,933,345 15,081,763
Non-Accrual Loans Status	The following table presents non-accrual loans excluding PCI loans at the dates indicated: December 31, 2015 December 31, 2014 # of loans amount # of loans amount (Dollars in thousands) Non-accrual: Multi-family 4 $ 3,467 2 $ 2,989 Commercial real estate 37 10,820 36 13,940 Commercial and industrial 17 9,225 11 2,903 Construction 4 792 7 4,345 Total commercial loans 62 24,304 56 24,177 Residential and consumer 500 91,122 406 84,182 Total non-accrual loans 562 $ 115,426 462 $ 108,359
Loans Individually Evaluated for Impairment by Class of Loans	The following tables present loans individually evaluated for impairment by portfolio segment as of December 31, 2015 and December 31, 2014 : December 31, 2015 Recorded Investment Unpaid Principal Balance Related Allowance Average Recorded Investment Interest Income Recognized (In thousands) With no related allowance: Multi-family $ 3,219 6,806 — 2,871 119 Commercial real estate 18,941 27,961 — 19,025 1,136 Commercial and industrial 5,155 5,160 — 3,575 200 Construction 2,504 6,412 — 4,288 226 Total commercial loans 29,819 46,339 — 29,759 1,681 Residential mortgage and consumer 8,020 12,433 — 7,611 463 With an allowance recorded: Multi-family — — — — — Commercial real estate — — — — — Commercial and industrial 4,240 4,271 2,409 4,389 194 Construction — — — — — Total commercial loans 4,240 4,271 2,409 4,389 194 Residential mortgage and consumer 14,908 13,695 1,782 16,424 476 Total: Multi-family 3,219 6,806 — 2,872 119 Commercial real estate 18,941 27,961 — 19,025 1,136 Commercial and industrial 9,395 9,431 2,409 7,964 394 Construction 2,504 6,412 — 4,288 226 Total commercial loans 34,059 50,610 2,409 34,149 1,875 Residential mortgage and consumer 22,928 26,128 1,782 24,035 939 Total impaired loans $ 56,987 76,738 4,191 58,184 2,814 December 31, 2014 Recorded Investment Unpaid Principal Balance Related Allowance Average Recorded Investment Interest Income Recognized (In thousands) With no related allowance: Multi-family $ 4,111 7,846 — 4,746 135 Commercial real estate 19,901 23,601 — 17,056 879 Commercial and industrial 3,310 3,310 — 1,985 152 Construction 6,798 9,292 — 13,609 410 Total commercial loans 34,120 44,049 — 37,396 1,576 Residential mortgage 6,755 8,830 — 6,606 370 With an allowance recorded: Multi-family — — — — — Commercial real estate 3,094 4,760 274 3,106 72 Commercial and industrial — — — — — Construction — — — — — Total commercial loans 3,094 4,760 274 3,106 72 Residential mortgage 16,530 16,882 1,865 16,547 507 Total: Multi-family 4,111 7,846 — 4,746 135 Commercial real estate 22,995 28,361 274 20,162 951 Commercial and industrial 3,310 3,310 — 1,985 152 Construction 6,798 9,292 — 13,609 410 Total commercial loans 37,214 48,809 274 40,502 1,648 Residential mortgage and consumer 23,285 25,712 1,865 23,153 877 Total impaired loans $ 60,499 74,521 2,139 63,655 2,525
Troubled Debt Restructured Loans	The following tables present the total troubled debt restructured loans at December 31, 2015 and December 31, 2014 . There were three residential PCI loans that were classified as TDRs and are included in the table below at December 31, 2015 . There were no PCI loans classified as a TDR for the period ended December 31, 2014 . December 31, 2015 Accrual Non-accrual Total # of loans Amount # of loans Amount # of loans Amount (Dollars in thousands) Commercial loans: Multi-family — $ — 2 $ 1,580 2 $ 1,580 Commercial real estate 5 13,161 9 5,826 14 18,987 Commercial and industrial 1 640 3 2,586 4 3,226 Construction 1 313 2 405 3 718 Total commercial loans 7 14,114 16 10,397 23 24,511 Residential mortgage and consumer 32 8,375 49 14,553 81 22,928 Total 39 $ 22,489 65 $ 24,950 104 $ 47,439 December 31, 2014 Accrual Non-accrual Total # of loans Amount # of loans Amount # of loans Amount (Dollars in thousands) Commercial loans: Multi-family 2 $ 1,122 — $ — 2 $ 1,122 Commercial real estate 8 15,250 1 3,197 9 18,447 Commercial and industrial 2 1,381 — — 2 1,381 Construction 2 3,066 — — 2 3,066 Total commercial loans 14 20,819 1 3,197 15 24,016 Residential mortgage and consumer 41 14,805 29 8,456 70 23,261 Total 55 $ 35,624 30 $ 11,653 85 $ 47,277
Schedule of Troubled Debt Restructurings	The following table presents information about troubled debt restructurings that occurred during the years ended December 31, 2015 and 2014 : Years Ended December 31, 2015 2014 Number of Loans Pre-modification Recorded Investment Post- modification Recorded Investment Number of Loans Pre-modification Recorded Investment Post- modification Recorded Investment (Dollars in thousands) Troubled Debt Restructings: Multi-family 1 $ 1,115 $ 1,115 — $ — $ — Commercial real estate 4 824 824 3 10,657 7,657 Construction 2 1,508 1,508 — — — Commercial and industrial 2 2,246 2,246 — — — Residential mortgage 19 3,413 3,413 11 3,217 3,217
Schedule of Troubled Debt Restructuring, Interest Yield	The following table presents information about pre and post modification interest yield for troubled debt restructurings which occurred during the years ended December 31, 2015 and 2014 : Years Ended December 31, 2015 2014 Number of Loans Pre-modification Interest Yield Post- modification Interest Yield Number of Loans Pre-modification Interest Yield Post- modification Interest Yield Troubled Debt Restructings: Multi-family 1 3.88 % 3.88 % — — % — % Commercial real estate 4 4.53 % 5.35 % 3 6.59 % 5.75 % Construction 2 4.97 % 4.97 % — — — Commercial and industrial 2 6.24 % 6.24 % — — — Residential mortgage 19 4.84 % 3.40 % 11 5.35 % 3.90 %

Office Properties and Equipme33

Office Properties and Equipment, Net (Tables)	12 Months Ended
	Dec. 31, 2015
Property, Plant and Equipment [Abstract]
Summary of Office Properties and Equipment	Office properties and equipment are summarized as follows: December 31, 2015 2014 (In thousands) Land $ 20,569 21,862 Office buildings 87,832 78,808 Leasehold improvements 79,898 66,857 Furniture, fixtures and equipment 77,096 68,420 Construction in process 12,075 17,121 277,470 253,068 Less accumulated depreciation and amortization 104,951 92,169 $ 172,519 160,899

Goodwill and Intangibles Asse34

Goodwill and Intangibles Assets (Tables)	12 Months Ended
	Dec. 31, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Intangible Assets and Goodwill	The following table summarizes net intangible assets and goodwill at December 31, 2015 and 2014 : December 31, 2015 December 31, 2014 (In thousands) Mortgage servicing rights $ 16,248 14,261 Core deposit premiums 11,332 14,683 Other 160 190 Total other intangible assets 27,740 29,134 Goodwill 77,571 77,571 Goodwill and intangible assets $ 105,311 106,705
Summary of Intangible Assets	The following table summarizes other intangible assets as of December 31, 2015 and December 31, 2014 : Gross Intangible Asset Accumulated Amortization Valuation Allowance Net Intangible Assets (In thousands) December 31, 2015 Mortgage Servicing Rights $ 23,411 (7,042 ) (121 ) 16,248 Core Deposit Premiums 25,058 (13,726 ) — 11,332 Other 300 (140 ) — 160 Total other intangible assets $ 48,769 (20,908 ) (121 ) 27,740 December 31, 2014 Mortgage Servicing Rights $ 23,925 (9,543 ) (121 ) 14,261 Core Deposit Premiums 25,058 (10,375 ) — 14,683 Other 300 (110 ) — 190 Total other intangible assets $ 49,283 (20,028 ) (121 ) 29,134
Schedule of Estimated Future Amortization Expense	The following presents the estimated future amortization expense of other intangible assets for the next five years: Mortgage Servicing Rights Core Deposit Premiums Other (In thousands) 2016 $ 473 $ 2,900 $ 30 2017 506 2,441 30 2018 522 1,983 30 2019 538 1,524 30 2020 552 1,109 30

Deposits (Tables)

Deposits (Tables)	12 Months Ended
	Dec. 31, 2015
Banking and Thrift [Abstract]
Summary of Deposits	Deposits are summarized as follows: December 31, 2015 2014 Weighted Average Rate Amount % of Total Weighted Average Rate Amount % of Total (In thousands) Checking accounts 0.17 % $ 4,636,025 32.96 % 0.20 % $ 3,892,839 31.98 % Money market deposits 0.67 % 3,861,317 27.46 % 0.71 % 3,390,238 27.85 % Savings 0.29 % 2,150,004 15.29 % 0.27 % 2,318,911 19.05 % Total transaction accounts 0.38 % 10,647,346 75.71 % 0.40 % 9,601,988 78.88 % Certificates of deposit 1.14 % 3,416,310 24.29 % 1.00 % 2,570,338 21.12 % Total Deposits 0.56 % $ 14,063,656 100.00 % 0.53 % $ 12,172,326 100.00 %
Scheduled Maturities Of Certificates Of Deposit	Scheduled maturities of certificates of deposit are as follows: December 31, 2015 2014 (In thousands) Within one year $ 2,586,076 1,450,655 One to two years 496,288 660,523 Two to three years 167,028 278,190 Three to four years 57,443 74,526 After four years 109,475 106,444 $ 3,416,310 2,570,338
Interest Expense On Deposits	Interest expense on deposits consists of the following: For the Years Ended December 31, 2015 2014 2013 (In thousands) Checking accounts $ 9,642 8,755 6,245 Money market deposits 23,562 13,664 7,537 Savings 6,976 6,639 6,320 Certificates of deposit 31,234 30,148 29,867 Total $ 71,414 59,206 49,969

Borrowed Funds (Tables)

Borrowed Funds (Tables)	12 Months Ended
	Dec. 31, 2015
Debt Disclosure [Abstract]
Summary of Borrowed Funds	Borrowed funds are summarized as follows: December 31, 2015 2014 Principal Weighted Average Rate Principal Weighted Average Rate (Dollars in thousands) Funds borrowed under repurchase agreements: FHLB $ 24,383 3.90% $ 25,071 3.90% Other brokers 131,924 1.89% 142,847 2.00% Total funds borrowed under repurchase agreements 156,307 2.21% 167,918 2.28% Other borrowed funds: FHLB advances 3,106,783 2.12% 2,598,186 2.24% Total borrowed funds $ 3,263,090 2.13% $ 2,766,104 2.24%
Borrowed Funds Scheduled Maturities	Borrowed funds had scheduled maturities as follows: December 31, 2015 2014 Principal Weighted Average Rate Principal Weighted Average Rate (Dollars in thousands) Within one year $ 500,000 1.99% $ 576,250 2.03% One to two years 249,383 3.00% 325,000 2.79% Two to three years 862,924 2.13% 250,071 3.00% Three to four years 469,782 1.78% 763,597 2.22% Four to five years 650,000 1.99% 444,994 1.78% After five years 531,001 2.30% 406,192 2.18% Total borrowed funds $ 3,263,090 2.13% $ 2,766,104 2.24%
Amortized Cost And Fair Value Of The Underlying Securities Used As Collateral For Securities Sold Under Agreements To Repurchase	The amortized cost and fair value of the underlying securities used as collateral for securities sold under agreements to repurchase are as follows: December 31, 2015 2014 (Dollars in thousands) Amortized cost of collateral: Mortgage-backed securities $ 475,984 195,890 Total amortized cost of collateral $ 475,984 195,890 Fair value of collateral: Mortgage-backed securities $ 481,401 198,502 Total fair value of collateral $ 481,401 198,502

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Summary of Components of Income Tax Expense (Benefit)	The components of income tax expense are as follows: Years Ended December 31, 2015 2014 2013 (In thousands) Current tax expense: Federal $ 87,748 77,029 76,692 State 14,804 7,508 7,881 102,552 84,537 84,573 Deferred tax (benefit) expense: Federal 4,310 (3,846 ) (16,887 ) State (7,490 ) (5,940 ) (3,931 ) (3,180 ) (9,786 ) (20,818 ) Total income tax expense $ 99,372 74,751 63,755
Summary of Reconciliation Between the Actual Income Tax Expense (Benefit) and the 'Expected' Amount Computed Using the Applicable Statutory Federal Income Tax Rate	The following table presents the reconciliation between the actual income tax expense and the “expected” amount computed using the applicable statutory federal income tax rate of 35% : Years Ended December 31, 2015 2014 2013 (In thousands) “Expected” federal income tax expense $ 98,307 72,265 61,525 State tax, net 4,753 1,019 2,567 Bank owned life insurance (1,382 ) (1,628 ) (1,014 ) Expiration of loss carryforward — — 645 Change in valuation allowance for federal deferred tax assets — — (645 ) Acquisition related net operating loss (4,076 ) — — ESOP fair market value adjustment 947 349 538 Non-deductible compensation 276 3,334 411 Non-deductible acquisition related expenses — — 297 Expiration of stock options 19 2 — Other 528 (590 ) (569 ) Total income tax expense $ 99,372 74,751 63,755
Summary of Deferred Tax Asset and Liability in Temporary Differences and Loss Carryforwards	The temporary differences and loss carryforwards which comprise the deferred tax asset and liability are as follows: December 31, 2015 2014 (In thousands) Deferred tax asset: Employee benefits $ 36,372 30,832 Deferred compensation 1,417 1,332 Premises and equipment 2,262 1,532 Allowance for loan losses 88,894 79,255 Net unrealized loss on securities 10,420 9,101 Net other than temporary impairment loss on securities 42,085 44,225 ESOP 3,695 2,921 Allowance for delinquent interest 13,071 12,379 Fair value adjustments related to acquisitions 31,986 38,309 Charitable contribution carryforward 5,823 5,685 Loan origination costs 7,127 10,821 Intangible assets 45 — Other 1,409 1,969 Gross deferred tax asset 244,606 238,361 Valuation allowance (346 ) (346 ) 244,260 238,015 Deferred tax liability: Intangible assets — 251 Mortgage servicing rights 6,893 5,866 Gross deferred tax liability 6,893 6,117 Net deferred tax asset $ 237,367 231,898

Benefit Plans (Tables)

Benefit Plans (Tables)	12 Months Ended
	Dec. 31, 2015
Compensation and Retirement Disclosure [Abstract]
Schedule Of Information Regarding Supplemental Executive Retirement Wage Replacement Plan And The Directors' Benefit Plan	The following table sets forth information regarding the Wage Replacement Plan and the directors’ defined benefit plan: December 31, 2015 2014 (In thousands) Change in benefit obligation: Benefit obligation at beginning of year $ 40,522 29,152 Service cost 3,096 2,319 Interest cost 1,497 1,322 (Gain) loss due to change in mortality assumption (778 ) 3,289 (Gain) loss due to change in discount rate (1,587 ) 4,816 Loss due to demographic changes 6,008 495 Benefits paid (871 ) (871 ) Benefit obligation at end of year 47,887 40,522 Funded status $ (47,887 ) (40,522 )
Schedule Of Accumulated Other Comprehensive Loss Related To Pension Plans On A Pre-Tax Basis	The components of accumulated other comprehensive loss related to pension plans, on a pre-tax basis, at December 31, 2015 and 2014 , are summarized in the following table. December 31, 2015 2014 (In thousands) Prior service cost $ — 49 Net actuarial gain 19,284 16,923 Total amounts recognized in accumulated other comprehensive income $ 19,284 16,972
Components Of Net Periodic Benefit Cost	The components of net periodic benefit cost are as follows: Years Ended December 31, 2015 2014 2013 (In thousands) Service cost $ 3,096 2,319 1,799 Interest cost 1,497 1,322 908 Amortization of: Prior service cost 49 98 98 Net gain 1,282 633 660 Total net periodic benefit cost $ 5,924 4,372 3,465
Schedule of Compensation Cost for Share-based Payment Arrangements, Allocation of Share-based Compensation Costs by Plan	The following table presents the share based compensation expense for the year ended December 31, 2015 2014 and 2013 . Upon completion of the mutual-to-stock conversion of Investors Bancorp, MHC on May 7, 2014, vesting accelerated for both stock options and restricted stock outstanding awards and all applicable expenses were recognized during the period. Years Ended December 31, 2015 2014 2013 (Dollars in thousands) Stock option expense $ 2,905 1,800 365 Restricted stock expense 6,314 11,900 3,100 Total share based compensation expense $ 9,219 13,700 3,465
Weighted Average Assumptions Used To Determine Net Periodic Benefit Cost	The weighted-average actuarial assumptions used in the plan determinations at December 31, 2015 and 2014 were as follows: December 31, 2015 2014 Discount rate 3.99 % 3.71 % Rate of compensation increase 4.36 % 4.19 % The following are the weighted average assumptions used to determine net periodic benefit cost: Years Ended December 31, 2015 2014 2013 Discount rate 3.71 % 4.53 % 3.56 % Rate of compensation increase 4.19 % 4.00 % 3.87 %
Estimated Future Benefit Payments	Estimated future benefit payments, which reflect expected future service, as appropriate for the next ten calendar years are as follows: Amount (In thousands) 2016 $ 1,175 2017 925 2018 906 2019 885 2020 2,882 2021 through 2025 22,174
Summary Of Non-Vested Options And Restricted Shares	The following is a summary of the status of the Company’s restricted shares as of December 31, 2015 and changes therein during the year then ended: Number of Shares Awarded Weighted Average Grant Date Fair Value Non-vested at December 31, 2014 — $ — Granted 6,849,832 12.54 Vested — — Forfeited (90,000 ) 12.54 Non-vested at December 31, 2015 6,759,832 $ 12.64
Summary Of Stock Option Activity And Related Information	The following is a summary of the Company’s stock option activity and related information for its option plan for the year ended December 31, 2015 : Number of Stock Options Weighted Average Exercise Price Weighted Average Remaining Contractual Life (in years) Aggregate Intrinsic Value Outstanding at December 31, 2014 9,092,584 $ 6.06 2.8 $ 46,984 Granted 11,576,611 12.54 9.9 Exercised (1,698,283 ) 5.96 1.6 Forfeited (161,419 ) 12.41 Expired (4,677 ) 9.90 Outstanding at December 31, 2015 18,804,816 $ 10.00 6.8 $ 46,996 Exercisable at December 31, 2015 7,366,289 $ 6.06 1.8 $ 46,975
Schedule Of Fair Value Of Option Grants Estimated On The Date Of Grant	The fair value of the option grants was estimated on the date of grant using the Black-Scholes option-pricing model with the following weighted average assumptions: December 31, 2015 2014 2013 Expected dividend yield 1.59 % 0.35 % 0.16 % Expected volatility 25.33 % 32.97 % 33.20 % Risk-free interest rate 1.96 % 1.69 % 1.38 % Expected option life 7.4 years 6.5 years 6.5 years The fair value of stock options granted on June 23, 2015 was estimated utilizing the Black-Scholes option pricing model using the following assumptions: Stock Options Granted Weighted average expected life (in years) 7.43 Weighted average risk-free rate of return 1.96 % Weighted average volatility 25.33 % Dividend yield 1.59 % Weighted average fair value of options granted $ 3.12

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
Projected Annual Minimum Rental Commitments	Amount (In thousands) 2016 $ 20,310 2017 20,055 2018 19,190 2019 18,588 2020 17,013 Thereafter 120,877 $ 216,033

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2015
Fair Value Disclosures [Abstract]
Fair Value, Assets Measured on Recurring Basis	The following tables provide the level of valuation assumptions used to determine the carrying value of our assets measured at fair value on a recurring basis at December 31, 2015 and December 31, 2014 . Carrying Value at December 31, 2015 Total Level 1 Level 2 Level 3 (In thousands) Securities available for sale: Equity securities $ 6,495 6,495 — — Mortgage-backed securities: Federal Home Loan Mortgage Corporation 547,451 — 547,451 — Federal National Mortgage Association 726,072 — 726,072 — Government National Mortgage Association 24,679 — 24,679 — Total mortgage-backed securities available-for-sale 1,298,202 — 1,298,202 — Total securities available-for-sale $ 1,304,697 6,495 1,298,202 — Carrying Value at December 31, 2014 Total Level 1 Level 2 Level 3 (In thousands) Securities available for sale: Equity securities $ 8,523 6,082 2,441 — Mortgage-backed securities: Federal Home Loan Mortgage Corporation 507,283 — 507,283 — Federal National Mortgage Association 681,992 — 681,992 — Government National Mortgage Association 126 — 126 — Total mortgage-backed securities available-for-sale 1,189,401 — 1,189,401 — Total securities available-for-sale $ 1,197,924 6,082 1,191,842 —
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation	The changes in Level 3 assets measured at fair value on a recurring basis for the years ended December 31, 2015 and 2014 are summarized below: Years Ended December 31, 2015 2014 (Dollars in thousands) Balance beginning of period (1) $ — 670 Total net (losses) gains for the period included in: Net income — 470 Other comprehensive income (loss) — (229 ) Sales — (911 ) Settlements — — Balance end of period $ — — (1) Represents a trust preferred security transferred to available for sale at its fair value on December 31, 2013 due to the impact of the Volcker Rule adopted in December 2013. The Volcker Rule requires specific treatment of certain collateralized debt obligation backed by trust preferred securities. The security was subsequently sold during the twelve months ended December 31, 2014
Carrying Value Of Our Assets Measured At Fair Value On A Non-Recurring Basis	The following tables provides the level of valuation assumptions used to determine the carrying value of our assets measured at fair value on a non-recurring basis at December 31, 2015 and December 31, 2014 . For the year ended December 31, 2015, there was no change to carrying value of MSR and impaired loans measured at fair value on a non-recurring basis. Security Type Valuation Technique Unobservable Input Range Weighted Average Carrying Value at December 31, 2015 Total Level 1 Level 2 Level 3 (In thousands) Other real estate owned Market comparable Lack of marketability 0.0% - 25.0% 8.90% $ 510 — — 510 $ 510 — — 510 Security Type Valuation Technique Unobservable Input Range Weighted Average Carrying Value at December 31, 2014 Total Level 1 Level 2 Level 3 (In thousands) MSR, net Estimated cash flow Prepayment speeds 5.70% - 29.40% 11.22% $ 13,081 — — 13,081 Other real estate owned Market comparable Lack of marketability 0.0% - 25.0% 15.87% 566 — — 566 $ 13,647 — — 13,647
Carrying Amounts And Estimated Fair Values	The carrying values and estimated fair values of the Company’s financial instruments are presented in the following table. December 31, 2015 Carrying Estimated Fair Value value Total Level 1 Level 2 Level 3 (In thousands) Financial assets: Cash and cash equivalents $ 148,904 148,904 148,904 — — Securities available-for-sale 1,304,697 1,304,697 6,495 1,298,202 — Securities held-to-maturity 1,844,223 1,888,686 — 1,810,869 77,817 Stock in FHLB 178,437 178,437 178,437 — — Loans held for sale 7,431 7,431 — 7,431 — Net loans 16,661,133 16,650,529 — — 16,650,529 Financial liabilities: Deposits, other than time deposits $ 10,647,346 10,647,346 10,647,346 — — Time deposits 3,416,310 3,414,528 — 3,414,528 — Borrowed funds 3,263,090 3,277,983 — 3,277,983 — December 31, 2014 Carrying Estimated Fair Value value Total Level 1 Level 2 Level 3 (In thousands) Financial assets: Cash and cash equivalents $ 230,961 230,961 230,961 — — Securities available-for-sale 1,197,924 1,197,924 6,082 1,191,842 — Securities held-to-maturity 1,564,479 1,609,365 — 1,544,129 65,236 Stock in FHLB 151,287 151,287 151,287 — — Loans held for sale 6,868 6,868 — 6,868 — Net loans 14,887,570 14,747,319 — — 14,747,319 Financial liabilities: Deposits, other than time deposits $ 9,601,988 9,601,988 9,601,988 — — Time deposits 2,570,338 2,580,572 — 2,580,572 — Borrowed funds 2,766,104 2,796,969 — 2,796,969 —

Regulatory Capital (Tables)

Regulatory Capital (Tables)	12 Months Ended
	Dec. 31, 2015
Regulatory Capital Requirements [Abstract]
Schedule of Regulatory Capital	The following is a summary of the Bank and the Company’s actual capital amounts and ratios as of December 31, 2015 compared to the FDIC minimum capital adequacy requirements and the FDIC requirements for classification as a well-capitalized institution. The information presented as of December 31, 2014 reflect the requirements in effect at that time, as the Basel III requirements became effective on January 1, 2015. Actual Minimum Capital Requirement To be Well Capitalized Under Prompt Corrective Action Provisions (1) Amount Ratio Amount Ratio Amount Ratio (Dollars in thousands) As of December 31, 2015: Bank: Tier 1 Leverage Ratio $ 2,558,334 12.41 % $ 824,607 4.00 % $ 1,030,759 5.00 % Common equity tier 1 risk-based 2,558,334 15.87 % 725,523 4.50 % 1,047,978 6.50 % Tier 1 Risk-Based Capital 2,558,334 15.87 % 967,364 6.00 % 1,289,819 8.00 % Total Risk-Based Capital 2,760,081 17.12 % 1,289,819 8.00 % 1,612,274 10.00 % Investors Bancorp, Inc: Tier 1 Leverage Ratio $ 3,259,928 15.80 % $ 825,139 4.00 % n/a n/a Common equity tier 1 risk-based 3,259,928 20.20 % 726,146 4.50 % n/a n/a Tier 1 Risk-Based Capital 3,259,928 20.20 % 968,194 6.00 % n/a n/a Total Risk-Based Capital 3,461,649 21.45 % 1,290,926 8.00 % n/a n/a Actual For Capital Adequacy Purposes To be Well Capitalized Under Prompt Corrective Action Provisions (1) Amount Ratio Amount Ratio Amount Ratio (Dollars in thousands) As of December 31, 2014: Bank: Tier 1 Leverage Ratio $ 2,339,572 12.79 % $ 731,884 4.00 % $ 914,855 5.00 % Tier 1 Risk-Based Capital 2,339,572 17.01 % 550,321 4.00 % 825,481 6.00 % Total Risk-Based Capital 2,511,897 18.26 % 1,100,641 8.00 % 1,375,802 10.00 % Investors Bancorp, Inc: Tier 1 Leverage Ratio $ 3,511,433 19.17 % $ 732,710 4.00 % n/a n/a Tier 1 Risk-Based Capital 3,511,433 25.48 % 551,181 4.00 % n/a n/a Total Risk-Based Capital 3,684,024 26.74 % 1,102,362 8.00 % n/a n/a (1) Prompt corrective action provisions do not apply to the Bank holding company.

Parent Company Only Financial42

Parent Company Only Financial Statements (Tables)	12 Months Ended
	Dec. 31, 2015
Condensed Financial Information of Parent Company Only Disclosure [Abstract]
Balance Sheets	Balance Sheets December 31, 2015 2014 (In thousands) Assets: Cash and due from bank $ 569,513 1,022,231 Securities available-for-sale, at estimated fair value 1,733 3,791 Investment in subsidiary 2,611,080 2,409,557 ESOP loan receivable 94,889 96,951 Other assets 45,898 52,499 Total Assets $ 3,323,113 3,585,029 Liabilities and Stockholders’ Equity: Total liabilities $ 11,466 7,174 Total stockholders’ equity 3,311,647 3,577,855 Total Liabilities and Stockholders’ Equity $ 3,323,113 3,585,029
Statements Of Operations	Statements of Operations Year Ended December 31, 2015 2014 2013 (In thousands) Income: Interest on ESOP loan receivable $ 3,151 2,499 1,125 Dividend from subsidiary — — 10,000 Interest on deposit with subsidiary 2 2 2 Interest and dividends on investments 65 64 49 Gain on securities transactions 1,682 145 89 4,900 2,710 11,265 Expenses: Interest expense 54 43 53 Other expenses 3,170 12,197 1,420 Income (loss) before income tax expense 1,676 (9,530 ) 9,792 Income tax (benefit) expense 540 (3,675 ) 233 Income (loss) before undistributed earnings of subsidiary 1,136 (5,855 ) 9,559 Equity in undistributed earnings of subsidiary 180,370 137,576 102,472 Net income $ 181,506 131,721 112,031
Other Comprehensive Income	Other Comprehensive Income Year Ended December 31, 2015 2014 2013 (In thousands) Net income $ 181,506 131,721 112,031 Other comprehensive income, net of tax: Unrealized gain on securities available-for-sale 433 1,482 1,316 Total other comprehensive income 433 1,482 1,316 Total comprehensive income $ 181,939 133,203 113,347
Statements Of Cash Flows	Statements of Cash Flows Year Ended December 31, 2015 2014 2013 (In thousands) Cash flows from operating activities: Net income $ 181,506 131,721 112,031 Adjustments to reconcile net income to net cash provided by operating activities: (Equity in undistributed earnings of subsidiary) (180,370 ) (137,576 ) (102,472 ) Contribution in stock to charitable foundation — 10,000 — Gain on securities transactions 1,682 145 89 Decrease in other assets 2,107 2,227 2,235 Increase in other liabilities 4,927 525 1,834 Net cash provided by operating activities 9,852 7,042 13,717 Cash flows from investing activities: Capital contributed to the Bank — (1,074,947 ) — Cash received net of cash paid for acquisition — 48 738 Purchase of investments available-for-sale — (493 ) (668 ) Redemption of equity securities available-for-sale 2,700 467 280 Principal collected on ESOP loan 2,062 3,093 1,101 Cash received from MHC merger — 11,307 — Net cash provided by (used in) investing activities 4,762 (1,060,525 ) 1,451 Cash flows from financing activities: Loan to ESOP — (66,553 ) — Proceeds from issuance of common stock — 2,149,893 — Proceeds from sale of treasury stock — 38,227 6,916 Purchase of treasury stock (382,922 ) (13,523 ) (1,531 ) Net tax benefit on stock awards 2,985 3,710 1,262 Dividends paid (87,395 ) (42,555 ) (22,404 ) Net cash (used in) provided by financing activities (467,332 ) 2,069,199 (15,757 ) Net (decrease) increase in cash and due from bank (452,718 ) 1,015,716 (589 ) Cash and due from bank at beginning of year 1,022,231 6,515 7,104 Cash and due from bank at end of year $ 569,513 1,022,231 6,515

Selected Quarterly Financial 43

Selected Quarterly Financial Data (Tables)	12 Months Ended
	Dec. 31, 2015
Quarterly Financial Information Disclosure [Abstract]
Summary of Certain Quarterly Financial Data	The following tables are a summary of certain quarterly financial data for the years ended December 31, 2015 and 2014 . 2015 Quarter Ended March 31 June 30 September 30 December 31 (In thousands, except per share data) Interest and dividend income $ 175,159 181,529 186,897 188,138 Interest expense 30,717 32,977 35,623 37,322 Net interest income 144,442 148,552 151,274 150,816 Provision for loan losses 9,000 7,000 5,000 5,000 Net interest income after provision for loan losses 135,442 141,552 146,274 145,816 Non-interest income 8,534 11,585 11,306 8,700 Non-interest expenses 76,909 79,836 85,921 85,666 Income before income tax expense 67,067 73,301 71,659 68,850 Income tax expense 25,120 26,939 22,865 24,448 Net income $ 41,947 46,362 48,794 44,402 Basic and diluted earnings per common share $ 0.12 0.14 0.15 0.14 2014 Quarter Ended March 31 June 30 September 30 December 31 (In thousands, except per share data) Interest and dividend income $ 158,625 164,089 167,058 171,090 Interest expense 29,434 29,326 29,212 30,919 Net interest income 129,191 134,763 137,846 140,171 Provision for loan losses 9,000 8,000 9,000 11,500 Net interest income after provision for loan losses 120,191 126,763 128,846 128,671 Non-interest income 11,942 10,173 9,872 9,874 Non-interest expenses 77,198 112,155 76,584 73,923 Income before income tax expense 54,935 24,781 62,134 64,622 Income tax expense 20,516 9,596 23,092 21,547 Net income $ 34,419 15,185 39,042 43,075 Basic earnings per common share $ 0.10 0.04 0.11 0.13 Diluted earnings per common share 0.10 0.04 0.11 0.12

Earnings Per Share (Tables)

Earnings Per Share (Tables)	12 Months Ended
	Dec. 31, 2015
Earnings Per Share [Abstract]
Summary Of Calculations And Reconciliation Of Basic To Diluted Earnings Per Share	The following is a summary of our earnings per share calculations and reconciliation of basic to diluted earnings per share. For the Year Ended December 31, 2015 2014 2013 Income Shares Per Share Amount Income Shares Per Share Amount Income Shares Per Share Amount (Dollars in thousands, except per share data) Net Income $ 181,505 $ 131,721 $ 112,031 Basic earnings per share: Income available to common stockholders $ 181,505 329,763,527 $ 0.55 $ 131,721 344,389,259 $ 0.38 $ 112,031 279,632,558 $ 0.40 Effect of dilutive common stock equivalents (1) 3,169,921 3,342,312 3,403,286 Diluted earnings per share: Income available to common stockholders $ 181,505 332,933,448 $ 0.55 $ 131,721 347,731,571 $ 0.38 $ 112,031 283,035,844 $ 0.40 (1) For the years ended December 31, 2015 , 2014 and 2013 , there were 18,200,877 , 142,953 , and 1,937,015 equity awards, respectively, that could potentially dilute basic earnings per share in the future that were not included in the computation of diluted earnings per share because to do so would have been anti-dilutive for the periods presented.

Comprehensive Income (Loss) (Ta

Comprehensive Income (Loss) (Tables)	12 Months Ended
	Dec. 31, 2015
Equity [Abstract]
Components of Comprehensive Income (Loss), Gross and Net Of Tax	The components of comprehensive income (loss), both gross and net of tax, are as follows: Year ended December 31, 2015 Year ended December 31, 2014 Year ended December 31, 2013 Gross Tax Net Gross Tax Net Gross Tax Net (Dollars in thousands) Net income $ 280,877 (99,372 ) 181,505 206,472 (74,751 ) 131,721 175,786 (63,755 ) 112,031 Other comprehensive income (loss): Change in funded status of retirement obligations (2,425 ) 970 (1,455 ) (8,402 ) 3,360 (5,042 ) 16 (6 ) 10 Unrealized (loss) gain on securities available-for-sale (7,982 ) 3,049 (4,933 ) 9,836 (3,884 ) 5,952 (21,930 ) 9,103 (12,827 ) Net Loss on Securities reclassified from available for sale to held to maturity — — — — — — (12,243 ) 5,001 (7,242 ) Accretion of loss on securities reclassified to held to maturity available for sale 2,448 (1,000 ) 1,448 2,918 (1,192 ) 1,726 1,670 (682 ) 988 Unrealized gain on security reclassified from held to maturity to available for sale — — — — — — 233 (95 ) 138 Reclassification adjustment for security (gains) losses included in net income (1,553 ) 6 (1,547 ) (233 ) 95 (138 ) (684 ) 279 (405 ) Noncredit related component other-than-temporary impairment on security — — — — — — 38 (16 ) 22 Other-than-temporary impairment accretion on debt securities 1,802 (736 ) 1,066 1,343 (549 ) 794 2,075 (848 ) 1,227 Total other comprehensive (loss) income (7,710 ) 2,289 (5,421 ) 5,462 (2,170 ) 3,292 (30,825 ) 12,736 (18,089 ) Total comprehensive income $ 273,167 (97,083 ) 176,084 211,934 (76,921 ) 135,013 144,961 (51,019 ) 93,942
Component of Accumulated Other Comprehensive Loss	The following table presents the after-tax changes in the balances of each component of accumulated other comprehensive loss for the years ended December 31, 2015 and 2014 : Change in funded status of retirement obligations Accretion of loss on securities reclassified to held to maturity Unrealized gain on securities available-for-sale Reclassification adjustment for losses included in net income Other-than- temporary impairment accretion on debt securities Total accumulated other comprehensive loss (Dollars in thousands) Balance - December 31, 2014 $ (10,911 ) (4,528 ) 7,851 — (14,816 ) (22,404 ) Net change (1,455 ) 1,448 (4,933 ) (1,547 ) 1,066 (5,421 ) Balance - December 31, 2015 $ (12,366 ) (3,080 ) 2,918 (1,547 ) (13,750 ) (27,825 ) Balance - December 31, 2013 $ (5,869 ) (6,254 ) 1,899 138 (15,610 ) (25,696 ) Net change (5,042 ) 1,726 5,952 (138 ) 794 3,292 Balance - December 31, 2014 $ (10,911 ) (4,528 ) 7,851 — (14,816 ) (22,404 ) The following table sets for information about amounts reclassified from accumulated other comprehensive loss to the consolidated statement of income and the affected line item in the statement where net income is presented. Year Ended December 31, 2015 2014 (In thousands) Reclassification adjustment for gains included in net income Gain on security transactions $ (1,553 ) (233 ) Change in funded status of retirement obligations (1) Compensation and fringe benefits: Adjustment of net obligation 2,512 (175 ) Amortization of net obligation or asset — 25 Amortization of prior service cost 49 125 Amortization of net gain 1,354 580 Compensation and fringe benefits 3,915 555 Total before tax 2,362 322 Income tax benefit (expense) 976 (205 ) Net of tax $ 1,386 527 (1) These accumulated other comprehensive loss components are included in the computations of net periodic cost for our defined benefit plans and other post-retirement benefit plan. See Note 11 for additional details.

Summary of Significant Accoun46

Summary of Significant Accounting Policies Summary of Significant Accounting Policies (Details)	May. 07, 2014USD ($)$ / sharesshares	May. 07, 2014$ / sharesshares	Oct. 11, 2005shares	Dec. 31, 2015USD ($)shares	Dec. 31, 2014USD ($)shares	Dec. 31, 2013shares	Jan. 31, 2007
Schedule of Accounting Policies [Line Items]
Proceeds from issuance of common stock | $	$ 2,150,000,000
Initial public stock offering (shares) | shares					213,963,274
Purchase of treasury stock, shares | shares				31,576,421	1,295,193	212,221
Cash equivalents, reserve requirement | $				$ 43,400,000	$ 39,100,000
Loan delinquent, not received payment, period, days				30 days
Accrual of income on loans discontinued when interest or principal payments are in arrears, period, days				90 days
Loans impairment analysis to include minimum commercial real estate, multi-family and construction loans outstanding balance | $				$ 1,000,000
Outstanding minimum balance of loans that are evaluated for impairment individually | $				1,000,000
Bank owned life insurance, carrying value consists of cash surrender value | $				152,500,000	155,800,000
Bank owned life insurance, carrying value consists of claims stabilization reserve | $				6,600,000	5,800,000
Carrying amount of goodwill | $				$ 77,571,000	$ 77,571,000
Matching contribution percentage of the first 6% contributed by participants under 401 (k) plan				50.00%
Employee contribution percentage that company matches 50%				6.00%
Maximum repayment period funds borrowed by ESOP to purchase common stock, years				30 years
Core Deposit Premium
Schedule of Accounting Policies [Line Items]
Core deposit premiums, amortized on an accelerated basis, years				10 years
Investors Bancorp, MHC
Schedule of Accounting Policies [Line Items]
Percentage of common stock owned							100.00%
Initial public stock offering (shares) | shares			165,353,151
Successor | IPO
Schedule of Accounting Policies [Line Items]
Initial public stock offering (shares) | shares	219,580,695
Share price (per share) | $ / shares	$ 10	$ 10
Shares issued in exchange of each share of converted stock (shares)		2.55
Shares issued as part of conversion (shares) | shares		137,560,968
Purchase of treasury stock, shares | shares		1,101,694			1,101,694
Investors Charitable Foundation | Successor | IPO
Schedule of Accounting Policies [Line Items]
Initial public stock offering (shares) | shares	1,000,000

Stock Transactions Stock Transa

Stock Transactions Stock Transactions (Details) $ / shares in Units, $ in Thousands	Jun. 09, 2015shares	Mar. 16, 2015shares	May. 07, 2014USD ($)$ / sharesshares	May. 07, 2014$ / sharesshares	Mar. 01, 2011	Oct. 11, 2005USD ($)shares	Sep. 28, 2012$ / shares	Dec. 31, 2015USD ($)$ / sharesshares	Dec. 31, 2014USD ($)$ / sharesshares	Dec. 31, 2013USD ($)shares
Stock Transactions [Line Items]
Initial public stock offering (shares)									213,963,274
Company contributed cash for common stock issued | $						$ 5,200
Stock issue expense, pre tax | $						20,700
Proceeds from issuance initial public offering | $						$ 509,700
Proceeds from issuance of common stock | $			$ 2,150,000
Purchase of treasury stock, shares								31,576,421	1,295,193	212,221
Percentage of shares to be repurchased	10.00%	5.00%			10.00%
Number of shares authorized to be repurchased	34,779,211	17,911,561						9,885,133
Stock repurchased during period, value | $								$ 382,922	$ 13,523	$ 1,531
Stock repurchase cost, per share | $ / shares								$ 12.13	$ 10.44
Dividends declared per share (usd per share) | $ / shares							$ 0.02
Common stock
Stock Transactions [Line Items]
Initial public stock offering (shares)						131,649,089
Public shares outstanding, percentage						43.74%
Investors bank employee stock ownership plan (shares)						10,847,883
Purchase of treasury stock, shares								6,849,832
Investors Bancorp, MHC
Stock Transactions [Line Items]
Initial public stock offering (shares)						165,353,151
Public shares outstanding, percentage						54.94%
Investors Bank Charitable Foundation
Stock Transactions [Line Items]
Initial public stock offering (shares)						3,949,473
Public shares outstanding, percentage						1.32%
Investors Bank
Stock Transactions [Line Items]
Proceeds from issuance initial public offering | $						$ 255,000
IPO | Successor
Stock Transactions [Line Items]
Initial public stock offering (shares)			219,580,695
Share price (per share) | $ / shares			$ 10	$ 10
Shares issued in exchange of each share of converted stock (shares)				2.55
Shares issued as part of conversion (shares)				137,560,968
Purchase of treasury stock, shares				1,101,694					1,101,694
Investors Charitable Foundation | IPO | Successor
Stock Transactions [Line Items]
Initial public stock offering (shares)			1,000,000

Business Combinations (Narrativ

Business Combinations (Narrative) (Details) $ in Thousands	Jan. 10, 2014USD ($)branchshares	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)	Dec. 31, 2013USD ($)
Business Acquisition [Line Items]
Bargain purchase gain		$ 0	$ 1,482	$ 0
Gateway Community Financial Corporation
Business Acquisition [Line Items]
Number of branches acquired | branch	4
Liabilities assumes, customer deposit	$ 254,700
Loans receivable	195,100
Intangibles assumed	1,900
Bargain purchase gain	$ 1,500
Investors Bancorp, MHC | Gateway Community Financial Corporation
Business Acquisition [Line Items]
Purchase price, common stock issued | shares	1,945,079

Business Combinations (Summary

Business Combinations (Summary of Estimated Fair Values of the Assets Acquired and Liabilities Assumed) (Details) - Gateway Community Financial Corporation $ in Millions	Jan. 10, 2014USD ($)
Business Acquisition [Line Items]
Cash and cash equivalents, net	$ 17.9
Securities available-for-sale	50.3
Loans receivable	195.1
Accrued interest receivable	0.7
Other real estate owned	0.4
Office properties and equipment, net	4.3
Intangible assets	1.9
Other assets	15.9
Total assets acquired	286.5
Deposits	(254.7)
Borrowed funds	(5.2)
Other liabilities	(3.1)
Total liabilities assumed	(263)
Net assets acquired	$ 23.5

Securities (Narrative) (Details

Securities (Narrative) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Investment [Line Items]
Carrying value of held to maturity security	$ 1,844,223,000	$ 1,564,479,000
Securities held-to-maturity	1,888,686,000	1,609,365,000
Accretion of loss on securities reclassified to held to maturity	0	0	$ 977,000
Non credit-related OTTI	23,200,000
Non credit-related OTTI, after-tax	13,800,000
Recognized net gains on available-for-sale securities		619,000
Gain (loss) on capital distributions of equity securities			88,600
Gross realized gain from sale of Available-for-sale securities		474,000	846,100
Proceeds from sale of Held-to-maturity securities		19,500,000
Gross realized gains from sale of Held-to-maturity securities		927,000
Sales from held-to-maturity, book value		18,300,000
Held-to-maturity securities, gross realized gains (losses)		$ 877,000
Percentage of held-to-maturity portfolio sold on the original investment		85.00%
Gain on securities transactions, net	$ 1,036,000	$ 1,546,000	772,000
Sale proceeds from sale of Available-for-sale securities,			56,000,000
Gross realized losses from sale of Available-for-sale securities,			$ 162,300
Corporate and other debt securities
Investment [Line Items]
Held-to-maturity securities, Term ( in years)	20 years
Carrying value of held to maturity security	$ 33,200,000
Securities held-to-maturity	71,100,000
Equity Securities
Investment [Line Items]
Gross realized gain from sale of Available-for-sale securities	1,500,000
Sale proceeds from sale of Available-for-sale securities,	2,600,000
U S Cap I V
Investment [Line Items]
Securities held-to-maturity	94,000
TruP Security
Investment [Line Items]
Held-to-maturity securities, gross realized gains (losses)	(646,000)
Gain on securities transactions, net		50,000
Available-for-sale Securities
Investment [Line Items]
Gain (loss) on capital distributions of equity securities	$ 145,000	$ 145,000

Securities (Summary of Securiti

Securities (Summary of Securities) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Carrying value	$ 1,302,122	$ 1,185,815
Gross unrecognized gains	8,496	14,301
Gross unrecognized losses	5,921	2,192
Estimated fair value	1,304,697	1,197,924
Equity Securities
Schedule of Available-for-sale Securities [Line Items]
Carrying value	5,778	6,887
Gross unrecognized gains	733	1,636
Gross unrecognized losses	16	0
Estimated fair value	6,495	8,523
Mortgage-backed securities:
Schedule of Available-for-sale Securities [Line Items]
Carrying value	1,296,344	1,178,928
Gross unrecognized gains	7,763	12,665
Gross unrecognized losses	5,905	2,192
Estimated fair value	1,298,202	1,189,401
Federal Home Loan Mortgage Corporation
Schedule of Available-for-sale Securities [Line Items]
Carrying value	546,652	503,268
Gross unrecognized gains	3,242	5,023
Gross unrecognized losses	2,443	1,008
Estimated fair value	547,451	507,283
Federal National Mortgage Association
Schedule of Available-for-sale Securities [Line Items]
Carrying value	724,851	675,535
Gross unrecognized gains	4,520	7,641
Gross unrecognized losses	3,299	1,184
Estimated fair value	726,072	681,992
Government National Mortgage Association
Schedule of Available-for-sale Securities [Line Items]
Carrying value	24,841	125
Gross unrecognized gains	1	1
Gross unrecognized losses	163	0
Estimated fair value	$ 24,679	$ 126

Securities (Summary - Held to M

Securities (Summary - Held to Maturity) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Schedule of Held-to-maturity Securities [Line Items]
Net unrealized losses	$ (100,200)	$ (108,817)	$ (112,235)	$ (114,514)
Carrying value of held to maturity security	1,844,223	1,564,479
Gross unrealized losses	9,202	3,483
Total, Estimated fair value	1,888,686	1,609,365
Government-sponsored enterprises
Schedule of Held-to-maturity Securities [Line Items]
Amortized cost	4,232	4,388
Net unrealized losses	0	0
Carrying value of held to maturity security	4,232	4,388
Gross unrealized gains	11	15
Gross unrealized losses	0	0
Total, Estimated fair value	4,243	4,403
Municipal bonds
Schedule of Held-to-maturity Securities [Line Items]
Amortized cost	43,058	24,320
Net unrealized losses	0	0
Carrying value of held to maturity security	43,058	24,320
Gross unrealized gains	1,307	1,001
Gross unrealized losses	0	0
Total, Estimated fair value	44,365	25,321
Corporate and other debt securities
Schedule of Held-to-maturity Securities [Line Items]
Amortized cost	58,358	58,487
Net unrealized losses	(23,245)	(25,047)
Carrying value of held to maturity security	35,113	33,440
Gross unrealized gains	$ 42,704	32,163
Gross unrealized losses		367
Total, Estimated fair value	$ 77,817	65,236
Debt Securities
Schedule of Held-to-maturity Securities [Line Items]
Amortized cost	105,648	87,195
Net unrealized losses	(23,245)	(25,047)
Carrying value of held to maturity security	82,403	62,148
Gross unrealized gains	44,022	33,179
Gross unrealized losses	0	367
Total, Estimated fair value	126,425	94,960
Federal Home Loan Mortgage Corporation
Schedule of Held-to-maturity Securities [Line Items]
Amortized cost	516,841	504,407
Net unrealized losses	(2,502)	(3,770)
Carrying value of held to maturity security	514,339	500,637
Gross unrealized gains	2,213	3,561
Gross unrealized losses	3,082	1,878
Total, Estimated fair value	513,470	502,320
Federal National Mortgage Association
Schedule of Held-to-maturity Securities [Line Items]
Amortized cost	1,228,845	978,261
Net unrealized losses	(2,705)	(3,885)
Carrying value of held to maturity security	1,226,140	974,376
Gross unrealized gains	7,305	11,629
Gross unrealized losses	6,120	1,218
Total, Estimated fair value	1,227,325	984,787
Government National Mortgage Association
Schedule of Held-to-maturity Securities [Line Items]
Amortized cost	21,330	27,136
Net unrealized losses	0	0
Carrying value of held to maturity security	21,330	27,136
Gross unrealized gains	125	0
Gross unrealized losses	0	20
Total, Estimated fair value	21,455	27,116
Federal housing authorities
Schedule of Held-to-maturity Securities [Line Items]
Amortized cost	11	182
Net unrealized losses	0	0
Carrying value of held to maturity security	11	182
Gross unrealized gains	0	0
Gross unrealized losses	0	0
Total, Estimated fair value	11	182
Mortgage-backed securities:
Schedule of Held-to-maturity Securities [Line Items]
Amortized cost	1,767,027	1,509,986
Net unrealized losses	(5,207)	(7,655)
Carrying value of held to maturity security	1,761,820	1,502,331
Gross unrealized gains	9,643	15,190
Gross unrealized losses	9,202	3,116
Total, Estimated fair value	1,762,261	1,514,405
Held-to-maturity Securities
Schedule of Held-to-maturity Securities [Line Items]
Amortized cost	1,872,675	1,597,181
Net unrealized losses	(28,452)	(32,702)
Carrying value of held to maturity security	1,844,223	1,564,479
Gross unrealized gains	53,665	48,369
Gross unrealized losses	9,202	3,483
Total, Estimated fair value	$ 1,888,686	$ 1,609,365

Securities (Amortized Cost and

Securities (Amortized Cost and Estimated Fair Value of Debt Securities by Contractual Maturity) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Schedule of Held-to-maturity Securities [Line Items]
Carrying value of held to maturity security	$ 1,844,223	$ 1,564,479
Total, Estimated fair value	1,888,686	$ 1,609,365
Debt Securities Other than Securities Pledged
Schedule of Held-to-maturity Securities [Line Items]
Due in one year or less, Amortized cost	40,136
Due after one year through five years, Amortized cost	2,363
Due after five years through ten years, Amortized cost	0
Due after ten years, Amortized cost	39,904
Carrying value of held to maturity security	82,403
Due in one year or less, Estimated fair value	40,136
Due after one year through five years, Estimated fair value	2,375
Due after five years through ten years, Estimated fair value	0
Due after ten years, Estimated fair value	83,914
Total, Estimated fair value	$ 126,425

Securities (Investment Securiti

Securities (Investment Securities, Continuous Unrealized Loss Position And Fair Value) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Available-for-sale, Estimated fair value
Less than 12 months	$ 668,613	$ 143,542
12 months or more	14,821	112,913
Total	683,434	256,455
Available-for-sale, Unrealized losses
Less than 12 months	5,472	476
12 months or more	449	1,716
Total	5,921	2,192
Held-to-maturity Securities, Estimated Fair Value
12 months or more	33,900	85,642
Less than 12 months	890,028	373,272
Total	923,928	458,914
Held-to-maturity Securities, Unrealized Losses
Less than 12 months	8,281	1,474
12 months or more	921	2,009
Total	9,202	3,483
Estimated fair value, Less than 12 months, Total	1,558,641	516,814
Unrealized losses, Less than 12 months, Total	13,753	1,950
Estimated fair value, 12 months or more, Total	48,721	198,555
Unrealized losses, 12 months or more, Total	1,370	3,725
Estimated fair value, Total	1,607,362	715,369
Unrealized losses, Total	15,123	5,675
Equity Securities
Available-for-sale, Estimated fair value
Less than 12 months	4,692
12 months or more	0
Total	4,692
Available-for-sale, Unrealized losses
Less than 12 months	16
12 months or more	0
Total	16
Corporate and other debt securities
Held-to-maturity Securities, Estimated Fair Value
12 months or more		233
Less than 12 months		674
Total		907
Held-to-maturity Securities, Unrealized Losses
Less than 12 months		40
12 months or more		327
Total		367
Federal Home Loan Mortgage Corporation
Available-for-sale, Estimated fair value
Less than 12 months	263,255	76,525
12 months or more	0	60,394
Total	263,255	136,919
Available-for-sale, Unrealized losses
Less than 12 months	2,443	426
12 months or more	0	582
Total	2,443	1,008
Held-to-maturity Securities, Estimated Fair Value
12 months or more	4,887	47,892
Less than 12 months	342,702	199,962
Total	347,589	247,854
Held-to-maturity Securities, Unrealized Losses
Less than 12 months	2,804	1,043
12 months or more	278	835
Total	3,082	1,878
Federal National Mortgage Association
Available-for-sale, Estimated fair value
Less than 12 months	375,792	67,017
12 months or more	14,821	52,519
Total	390,613	119,536
Available-for-sale, Unrealized losses
Less than 12 months	2,850	50
12 months or more	449	1,134
Total	3,299	1,184
Held-to-maturity Securities, Estimated Fair Value
12 months or more	29,013
Less than 12 months	547,326
Total	576,339
Held-to-maturity Securities, Unrealized Losses
Less than 12 months	5,477
12 months or more	643
Total	6,120
Government National Mortgage Association
Available-for-sale, Estimated fair value
Less than 12 months	$ 24,874
12 months or more
Total	$ 24,874
Available-for-sale, Unrealized losses
Less than 12 months	$ 163
12 months or more
Total	$ 163
Held-to-maturity Securities, Estimated Fair Value
12 months or more		0
Less than 12 months		27,116
Total		27,116
Held-to-maturity Securities, Unrealized Losses
Less than 12 months		20
12 months or more		0
Total		20
Mortgage-backed securities:
Available-for-sale, Estimated fair value
Less than 12 months	663,921	143,542
12 months or more	14,821	112,913
Total	678,742	256,455
Available-for-sale, Unrealized losses
Less than 12 months	5,456	476
12 months or more	449	1,716
Total	5,905	2,192
Held-to-maturity Securities, Estimated Fair Value
12 months or more	33,900	85,409
Less than 12 months	890,028	372,598
Total	923,928	458,007
Held-to-maturity Securities, Unrealized Losses
Less than 12 months	8,281	1,434
12 months or more	921	1,682
Total	$ 9,202	3,116
Federal National Mortgage Association [Member]
Held-to-maturity Securities, Estimated Fair Value
12 months or more		37,517
Less than 12 months		145,520
Total		183,037
Held-to-maturity Securities, Unrealized Losses
Less than 12 months		371
12 months or more		847
Total		$ 1,218

Securities (Changes in Credit L

Securities (Changes in Credit Loss Component of the Impairment Loss of Debt Securities for Other-than-Temporary Impairment Recognized in Earnings) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Investments, Debt and Equity Securities [Abstract]
Balance of credit related OTTI, beginning of period	$ 108,817	$ 112,235	$ 114,514
Initial credit impairments	0	0	0
Subsequent credit impairments	0	0	977
Accretion of credit loss impairment due to an increase in expected cash flows	(3,804)	(3,418)	(3,256)
Reduction for securities sold or paid off during the period	(4,813)	0	0
Balance of credit related OTTI, end of period	$ 100,200	$ 108,817	$ 112,235

Loans Receivable, Net (Narrativ

Loans Receivable, Net (Narrative) (Details)	3 Months Ended								12 Months Ended
	Dec. 31, 2015USD ($)	Sep. 30, 2015USD ($)	Jun. 30, 2015USD ($)	Mar. 31, 2015USD ($)	Dec. 31, 2014USD ($)	Sep. 30, 2014USD ($)	Jun. 30, 2014USD ($)	Mar. 31, 2014USD ($)	Dec. 31, 2015USD ($)loan	Dec. 31, 2014USD ($)loan	Dec. 31, 2013USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
PCI loans acquired									$ 400,000
Outstanding minimum balance of loans that are evaluated for impairment individually	$ 1,000,000								$ 1,000,000
Residential mortgage loans, appraisal update period, years									2 years
PCI loans	11,089,000				$ 17,789,000				$ 11,089,000	$ 17,789,000
Allowance for loan losses, individually evaluated for impairment	4,191,000				2,139,000				$ 4,191,000	$ 2,139,000
Number of non-accrual loans | loan									562	462
Loans that are 90 days past due and still accruing	0								$ 0
Provision for loan losses	5,000,000	$ 5,000,000	$ 7,000,000	$ 9,000,000	11,500,000	$ 9,000,000	$ 8,000,000	$ 9,000,000	26,000,000	$ 37,500,000	$ 50,500,000
Loans, Individually evaluated for impairment	56,987,000				60,499,000				56,987,000	60,499,000
Interest income received and recognized on loans									3,800,000	2,500,000
Charges-offs for collateral dependent TDRs									$ 12,216,000	$ 18,244,000
Post- modification Interest Yield									4.97%	0.00%
Weighted average modified yield									4.97%	0.00%
Loans modified as TDR in the last 12 months for which there was a default payment | loan									0
Troubled debt restructured, number of loans | loan									104	85
Recorded investment	47,439,000				47,277,000				$ 47,439,000	$ 47,277,000
Transfer of loans to loans held for sale									347,955,000	32,411,000	$ 0
Collateral Dependant TDRs
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses, individually evaluated for impairment	1,773,000				1,865,000				1,773,000	1,865,000
Charges-offs for collateral dependent TDRs									0	3,000,000
Residential Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
TDR number of current loans classified as non-accrual, amount	3,300,000								$ 3,300,000
Number of non-accrual loans | loan									11
Transfer of loans to loans held for sale									$ 347,300,000
Sale of non performing and PCI loans										32,400,000
Commercial and Industrial Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses, individually evaluated for impairment	2,409,000				0				$ 2,409,000	$ 0
Number of current loans classified as non-accrual, TDR | loan									2
TDR number of current loans classified as non-accrual, amount	2,200,000								$ 2,200,000
Number of non-accrual loans | loan									17	11
Loans, Individually evaluated for impairment	9,395,000				3,310,000				$ 9,395,000	$ 3,310,000
Charges-offs for collateral dependent TDRs									$ 516,000	$ 2,447,000
Post- modification Interest Yield									6.24%	0.00%
Weighted average modified yield									6.24%	0.00%
Troubled debt restructured, number of loans | loan									4	2
Recorded investment	3,226,000				1,381,000				$ 3,226,000	$ 1,381,000
Residential Mortgage Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Delinquency period in days									90 days
Allowance for loan losses, individually evaluated for impairment	1,773,000				1,865,000				$ 1,773,000	1,865,000
Number of current loans classified as non-accrual, TDR | loan									5
TDR number of current loans classified as non-accrual, amount	2,900,000								$ 2,900,000
Loans, Individually evaluated for impairment	22,539,000				23,285,000				22,539,000	23,285,000
Charges-offs for collateral dependent TDRs									$ 9,526,000	$ 7,715,000
Post- modification Interest Yield									3.40%	3.90%
Weighted average modified yield									4.84%	5.35%
Troubled debt restructured, number of loans | loan									81	70
Recorded investment	22,928,000				23,261,000				$ 22,928,000	$ 23,261,000
TDR loans classified as non-accrual, 30-89 days delinquent, amount	1,500,000								$ 1,500,000
TDR loans classified as non-accrual, 30-89 days delinquent, number of loans | loan									10
Residential Mortgage Loans | Maximum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Delinquency period in days									89 days
Residential Mortgage Loans | Minimum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Delinquency period in days									30 days
Commercial Real Estate Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses, individually evaluated for impairment	0				274,000				$ 0	$ 274,000
Number of current loans classified as non-accrual, TDR | loan									2
TDR number of current loans classified as non-accrual, amount	240,000								$ 240,000
Number of non-accrual loans | loan									37	36
Loans, Individually evaluated for impairment	18,941,000				22,995,000				$ 18,941,000	$ 22,995,000
Charges-offs for collateral dependent TDRs									$ 1,021,000	$ 6,147,000
Post- modification Interest Yield									5.35%	5.75%
Weighted average modified yield									4.53%	6.59%
Troubled debt restructured, number of loans | loan									14	9
Recorded investment	18,987,000				18,447,000				$ 18,987,000	$ 18,447,000
Multi- Family Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses, individually evaluated for impairment	0				0				$ 0	$ 0
Number of current loans classified as non-accrual, TDR | loan									1
TDR number of current loans classified as non-accrual, amount	1,000,000								$ 1,000,000
Number of non-accrual loans | loan									4	2
Loans, Individually evaluated for impairment	3,219,000				4,111,000				$ 3,219,000	$ 4,111,000
Charges-offs for collateral dependent TDRs									$ 284,000	$ 323,000
Post- modification Interest Yield									3.88%	0.00%
Weighted average modified yield									3.88%	0.00%
Troubled debt restructured, number of loans | loan									2	2
Recorded investment	1,580,000				1,122,000				$ 1,580,000	$ 1,122,000
Construction Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses, individually evaluated for impairment	0				0				$ 0	$ 0
Number of non-accrual loans | loan									4	7
Loans, Individually evaluated for impairment	2,504,000				6,798,000				$ 2,504,000	$ 6,798,000
Charges-offs for collateral dependent TDRs									$ 466,000	$ 640,000
Loans modified as TDR in the last 12 months for which there was a default payment | loan									1
Recorded investment									$ 225,000
Troubled debt restructured, number of loans | loan									3	2
Recorded investment	718,000				3,066,000				$ 718,000	$ 3,066,000
Sale of non performing and PCI loans										$ 552,000
Commercial Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding minimum balance of loans to be evaluated for impairment individually	1,000,000								1,000,000
Outstanding minimum balance of loans that are evaluated for impairment individually	1,000,000								$ 1,000,000
Number of non-accrual loans | loan									62	56
Troubled debt restructured, number of loans | loan									23	15
Recorded investment	24,511,000				24,016,000				$ 24,511,000	$ 24,016,000
Commercial Real Estate Construction And Multi Family [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding minimum balance of loans to be evaluated for impairment individually	500,000								500,000
Outstanding minimum balance of loans that are evaluated for impairment individually	2,000,000								$ 2,000,000
Residential And Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of current loans classified as non-accrual, TDR | loan									15
TDR number of current loans classified as non-accrual, amount	3,400,000								$ 3,400,000
Number of non-accrual loans | loan									500	406
PCI Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Transfer of Loans Held-for-sale to Portfolio Loans									$ 1,900,000
Marathon Banking Corporation and Marathon National Bank of New York | PCI Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
PCI loans	11,100,000				17,800,000				11,100,000	$ 17,800,000
Upto 90 Days | Marathon Banking Corporation and Marathon National Bank of New York | PCI Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
PCI loans	9,000,000				9,200,000				9,000,000	9,200,000
More than 90 Days | Marathon Banking Corporation and Marathon National Bank of New York | PCI Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
PCI loans	2,100,000				$ 8,600,000				$ 2,100,000	8,600,000
Special Mention Residential [Member] | Maximum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Delinquency period in days									89 days
Special Mention Residential [Member] | Minimum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Delinquency period in days									60 days
Substandard Residential [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Delinquency period in days									90 days
Watch | Maximum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Delinquency period in days									59 days
Watch | Minimum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Delinquency period in days									30 days
Nonperforming Financial Instruments [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Charges-offs for collateral dependent TDRs									$ 4,500,000
Transfer of loans to loans held for sale									20,900,000
Gain on Loan Transactions, Net [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gain (loss) on sales, net									611,000
Collateral Pledged [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Provision for loan losses									4,200,000	$ 2,100,000
Financing Receivables, 30 to 89 Days Past Due [Member] | Commercial and Industrial Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
TDR number of current loans classified as non-accrual, amount	400,000								$ 400,000
Number of non-accrual loans | loan									1
Financing Receivables, 30 to 89 Days Past Due [Member] | Commercial Real Estate Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
TDR number of current loans classified as non-accrual, amount	$ 2,300,000								$ 2,300,000
Number of non-accrual loans | loan									5

Loans Receivable, Net (Details)

Loans Receivable, Net (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Receivables [Abstract]
Multi-family loans	$ 6,255,904	$ 5,048,477
Commercial real estate loans	3,821,950	3,139,824
Commercial and industrial loans	1,044,329	544,402
Construction loans	224,057	143,664
Total commercial loans	11,346,240	8,876,367
Residential mortgage loans	5,037,898	5,764,896
Consumer and other loans	496,103	440,500
Total loans excluding PCI loans	16,880,241	15,081,763
PCI loans	11,089	17,789
Net unamortized premiums and deferred loan costs	(11,692)	(11,698)
Allowance for loan losses	(218,505)	(200,284)	$ (173,928)	$ (142,172)
Net loans	$ 16,661,133	$ 14,887,570

Loans Receivable, Net (Purchase

Loans Receivable, Net (Purchased Credit Impaired Loans) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Jan. 10, 2014
Schedule of Available-for-sale Securities [Line Items]
PCI loans, outstanding	$ 11,089	$ 17,789
PCI Loans
Accretable Yeild [Roll Forward]
Balance, beginning of period	971	4,154
Acquisitions	0	216
Accretion	(522)	(3,399)
Net reclassification from non-accretable difference	0	0
Balance, ending of period	$ 449	$ 971
Gateway Community Financial Corporation
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Acquired During Period [Abstract]
Contractually required principal and interest			$ 4,172
Contractual cash flows not expected to be collected (non-accretable difference)			(1,024)
Expected cash flows to be collected			3,148
Interest component of expected cash flows (accretable yield)			(216)
Fair value of acquired loans			$ 2,932

Loans Receivable, Net (Summary

Loans Receivable, Net (Summary of Analysis of the Allowance for Loan Losses) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of year				$ 200,284				$ 173,928	$ 200,284	$ 173,928	$ 142,172
Loans charged off									(12,216)	(18,244)	(22,610)
Recoveries									4,437	7,100	3,866
Net charge-offs									(7,779)	(11,144)	(18,744)
Provision for loan losses	$ 5,000	$ 5,000	$ 7,000	$ 9,000	$ 11,500	$ 9,000	$ 8,000	$ 9,000	26,000	37,500	50,500
Balance at end of year	$ 218,505				$ 200,284				$ 218,505	$ 200,284	$ 173,928

Loans Receivable, Net (Summar60

Loans Receivable, Net (Summary of Allowance for Loan Losses and the Recorded Investment in Loans by Portfolio Segment And Based On Impairment Method) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, Beginning balance	$ 200,284	$ 173,928
Allowance for loan losses, Charge-offs	(12,216)	(18,244)
Allowance for loan losses, Recoveries	4,437	7,100
Allowance for loan losses, Provision	26,000	37,500
Allowance for loan losses, Ending balance	218,505	200,284
Allowance for loan losses, Individually evaluated for impairment	4,191	2,139
Allowance for loan losses, Collectively evaluated for impairment	214,314	198,145
Loans, Individually evaluated for impairment	56,987	60,499
Loans, Collectively evaluated for impairment	16,823,254	15,021,264
Ending Balance	16,891,330	15,099,552
Multi- Family Loans
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, Beginning balance	71,147	42,103
Allowance for loan losses, Charge-offs	(284)	(323)
Allowance for loan losses, Recoveries	445	3,784
Allowance for loan losses, Provision	16,915	25,583
Allowance for loan losses, Ending balance	88,223	71,147
Allowance for loan losses, Individually evaluated for impairment	0	0
Allowance for loan losses, Collectively evaluated for impairment	88,223	71,147
Loans, Individually evaluated for impairment	3,219	4,111
Loans, Collectively evaluated for impairment	6,252,685	5,044,366
Ending Balance	6,255,904	5,049,114
Commercial Real Estate Loans
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, Beginning balance	44,030	46,657
Allowance for loan losses, Charge-offs	(1,021)	(6,147)
Allowance for loan losses, Recoveries	807	201
Allowance for loan losses, Provision	3,183	3,319
Allowance for loan losses, Ending balance	46,999	44,030
Allowance for loan losses, Individually evaluated for impairment	0	274
Allowance for loan losses, Collectively evaluated for impairment	46,999	43,756
Loans, Individually evaluated for impairment	18,941	22,995
Loans, Collectively evaluated for impairment	3,803,009	3,116,829
Ending Balance	3,829,099	3,147,153
Commercial and Industrial Loans
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, Beginning balance	20,759	9,273
Allowance for loan losses, Charge-offs	(516)	(2,447)
Allowance for loan losses, Recoveries	295	516
Allowance for loan losses, Provision	20,047	13,417
Allowance for loan losses, Ending balance	40,585	20,759
Allowance for loan losses, Individually evaluated for impairment	2,409	0
Allowance for loan losses, Collectively evaluated for impairment	38,176	20,759
Loans, Individually evaluated for impairment	9,395	3,310
Loans, Collectively evaluated for impairment	1,034,934	541,092
Ending Balance	1,044,385	544,458
Construction Loans
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, Beginning balance	6,488	8,947
Allowance for loan losses, Charge-offs	(466)	(640)
Allowance for loan losses, Recoveries	317	799
Allowance for loan losses, Provision	455	(2,618)
Allowance for loan losses, Ending balance	6,794	6,488
Allowance for loan losses, Individually evaluated for impairment	0	0
Allowance for loan losses, Collectively evaluated for impairment	6,794	6,488
Loans, Individually evaluated for impairment	2,504	6,798
Loans, Collectively evaluated for impairment	221,553	136,866
Ending Balance	225,843	148,396
Residential Mortgage Loans
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, Beginning balance	47,936	51,760
Allowance for loan losses, Charge-offs	(9,526)	(7,715)
Allowance for loan losses, Recoveries	2,295	1,783
Allowance for loan losses, Provision	(9,262)	2,108
Allowance for loan losses, Ending balance	31,443	47,936
Allowance for loan losses, Individually evaluated for impairment	1,773	1,865
Allowance for loan losses, Collectively evaluated for impairment	29,670	46,071
Loans, Individually evaluated for impairment	22,539	23,285
Loans, Collectively evaluated for impairment	5,015,359	5,741,611
Ending Balance	5,039,543	5,769,477
Consumer and Other Loans
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, Beginning balance	3,347	2,161
Allowance for loan losses, Charge-offs	(403)	(972)
Allowance for loan losses, Recoveries	278	17
Allowance for loan losses, Provision	(67)	2,141
Allowance for loan losses, Ending balance	3,155	3,347
Allowance for loan losses, Individually evaluated for impairment	9	0
Allowance for loan losses, Collectively evaluated for impairment	3,146	3,347
Loans, Individually evaluated for impairment	389	0
Loans, Collectively evaluated for impairment	495,714	440,500
Ending Balance	496,556	440,954
Unallocated
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, Beginning balance	6,577	13,027
Allowance for loan losses, Charge-offs	0	0
Allowance for loan losses, Recoveries	0	0
Allowance for loan losses, Provision	(5,271)	(6,450)
Allowance for loan losses, Ending balance	1,306	6,577
Allowance for loan losses, Individually evaluated for impairment	0	0
Allowance for loan losses, Collectively evaluated for impairment	1,306	6,577
Loans, Individually evaluated for impairment	0	0
Loans, Collectively evaluated for impairment	0	0
Ending Balance	0	0
Receivables Acquired with Deteriorated Credit Quality [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, Beginning balance	0
Allowance for loan losses, Ending balance	0	0
Ending Balance	11,089	17,789
Receivables Acquired with Deteriorated Credit Quality [Member] | Multi- Family Loans
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, Beginning balance	0
Allowance for loan losses, Ending balance	0	0
Ending Balance	0	637
Receivables Acquired with Deteriorated Credit Quality [Member] | Commercial Real Estate Loans
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, Beginning balance	0
Allowance for loan losses, Ending balance	0	0
Ending Balance	7,149	7,329
Receivables Acquired with Deteriorated Credit Quality [Member] | Commercial and Industrial Loans
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, Beginning balance	0
Allowance for loan losses, Ending balance	0	0
Ending Balance	56	56
Receivables Acquired with Deteriorated Credit Quality [Member] | Construction Loans
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, Beginning balance	0
Allowance for loan losses, Ending balance	0	0
Ending Balance	1,786	4,732
Receivables Acquired with Deteriorated Credit Quality [Member] | Residential Mortgage Loans
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, Beginning balance	$ 0
Allowance for loan losses, Ending balance		0
Ending Balance	$ 1,645	4,581
Receivables Acquired with Deteriorated Credit Quality [Member] | Consumer and Other Loans
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, Beginning balance	0
Allowance for loan losses, Ending balance	0	0
Ending Balance	453	454
Receivables Acquired with Deteriorated Credit Quality [Member] | Unallocated
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, Beginning balance	0
Allowance for loan losses, Ending balance	0	0
Ending Balance	$ 0	$ 0

Loans Receivable, Net (Schedule

Loans Receivable, Net (Schedule of Risk Category of Loans by Class of Loans) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans	$ 16,880,241	$ 15,081,763
Multi- Family Loans
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans	6,255,904	5,048,477
Commercial Real Estate Loans
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans	3,821,950	3,139,824
Commercial and Industrial Loans
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans	1,044,329	544,402
Construction Loans
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans	224,057	143,664
Commercial Loan
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans	11,346,240	8,876,367
Residential Mortgage Loans
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans	5,037,898	5,764,896
Consumer and Other Loans
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans	496,103	440,500
Pass
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans	15,703,003	14,079,948
Pass | Multi- Family Loans
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans	5,876,425	4,710,124
Pass | Commercial Real Estate Loans
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans	3,411,876	2,757,949
Pass | Commercial and Industrial Loans
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans	793,527	405,021
Pass | Construction Loans
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans	207,499	134,356
Pass | Commercial Loan
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans	10,289,327	8,007,450
Pass | Residential Mortgage Loans
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans	4,930,961	5,641,184
Pass | Consumer and Other Loans
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans	482,715	431,314
Watch
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans	921,721	663,229
Watch | Multi- Family Loans
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans	325,414	247,921
Watch | Commercial Real Estate Loans
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans	331,429	276,660
Watch | Commercial and Industrial Loans
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans	223,474	110,374
Watch | Construction Loans
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans	12,833	2,228
Watch | Commercial Loan
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans	893,150	637,183
Watch | Residential Mortgage Loans
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans	24,584	22,059
Watch | Consumer and Other Loans
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans	3,987	3,987
Special Mention
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans	83,303	123,193
Special Mention | Multi- Family Loans
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans	17,033	62,886
Special Mention | Commercial Real Estate Loans
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans	38,265	29,248
Special Mention | Commercial and Industrial Loans
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans	13,782	20,321
Special Mention | Construction Loans
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans	0	2,075
Special Mention | Commercial Loan
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans	69,080	114,530
Special Mention | Residential Mortgage Loans
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans	13,796	7,657
Special Mention | Consumer and Other Loans
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans	427	1,006
Substandard
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans	172,214	215,393
Substandard | Multi- Family Loans
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans	37,032	27,546
Substandard | Commercial Real Estate Loans
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans	40,380	75,967
Substandard | Commercial and Industrial Loans
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans	13,546	8,686
Substandard | Construction Loans
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans	3,725	5,005
Substandard | Commercial Loan
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans	94,683	117,204
Substandard | Residential Mortgage Loans
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans	68,557	93,996
Substandard | Consumer and Other Loans
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans	8,974	4,193
Doubtful
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans	0	0
Doubtful | Multi- Family Loans
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans	0	0
Doubtful | Commercial Real Estate Loans
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans	0	0
Doubtful | Commercial and Industrial Loans
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans	0	0
Doubtful | Construction Loans
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans		0
Doubtful | Commercial Loan
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans	0	0
Doubtful | Residential Mortgage Loans
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans	0	0
Doubtful | Consumer and Other Loans
Financing Receivable, Recorded Investment [Line Items]
Risk category of loans	$ 0	$ 0

Loans Receivable, Net (Payment

Loans Receivable, Net (Payment Status of the Recorded Investment in Past Due Loans) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	$ 157,207	$ 148,418
Current	16,723,034	14,933,345
Total Loans Receivable	16,880,241	15,081,763
Multi- Family Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	16,122	3,926
Current	6,239,782	5,044,551
Total Loans Receivable	6,255,904	5,048,477
Commercial Real Estate Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	10,952	21,284
Current	3,810,998	3,118,540
Total Loans Receivable	3,821,950	3,139,824
Commercial and Industrial Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	5,343	4,090
Current	1,038,986	540,312
Total Loans Receivable	1,044,329	544,402
Construction Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	792	4,345
Current	223,265	139,319
Total Loans Receivable	224,057	143,664
Commercial Loan
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	33,209	33,645
Current	11,313,031	8,842,722
Total Loans Receivable	11,346,240	8,876,367
Residential Mortgage Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	110,608	108,222
Current	4,927,290	5,656,674
Total Loans Receivable	5,037,898	5,764,896
Consumer and Other Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	13,390	6,551
Current	482,713	433,949
Total Loans Receivable	496,103	440,500
30-59 Days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	50,443	33,102
30-59 Days | Multi- Family Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	14,236	698
30-59 Days | Commercial Real Estate Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	4,171	6,566
30-59 Days | Commercial and Industrial Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	957	792
30-59 Days | Construction Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
30-59 Days | Commercial Loan
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	19,364	8,056
30-59 Days | Residential Mortgage Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	27,092	23,712
30-59 Days | Consumer and Other Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	3,987	1,334
60-89 Days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	15,735	11,318
60-89 Days | Multi- Family Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	239
60-89 Days | Commercial Real Estate Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	352	778
60-89 Days | Commercial and Industrial Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	395
60-89 Days | Construction Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
60-89 Days | Commercial Loan
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	352	1,412
60-89 Days | Residential Mortgage Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	14,956	8,900
60-89 Days | Consumer and Other Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	427	1,006
Greater than 90 Days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	91,029	103,998
Greater than 90 Days | Multi- Family Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	1,886	2,989
Greater than 90 Days | Commercial Real Estate Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	6,429	13,940
Greater than 90 Days | Commercial and Industrial Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	4,386	2,903
Greater than 90 Days | Construction Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	792	4,345
Greater than 90 Days | Commercial Loan
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	13,493	24,177
Greater than 90 Days | Residential Mortgage Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	68,560	75,610
Greater than 90 Days | Consumer and Other Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	$ 8,976	$ 4,211

Loans Receivable, Net (Non-Accr

Loans Receivable, Net (Non-Accrual Loans Status) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2015USD ($)loan	Dec. 31, 2014USD ($)loan
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-accrual: # of loans | loan	562	462
Non-accrual, Amount | $	$ 115,426	$ 108,359
Multi- Family Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-accrual: # of loans | loan	4	2
Non-accrual, Amount | $	$ 3,467	$ 2,989
Commercial Real Estate Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-accrual: # of loans | loan	37	36
Non-accrual, Amount | $	$ 10,820	$ 13,940
Commercial and Industrial Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-accrual: # of loans | loan	17	11
Non-accrual, Amount | $	$ 9,225	$ 2,903
Construction Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-accrual: # of loans | loan	4	7
Non-accrual, Amount | $	$ 792	$ 4,345
Commercial Loan
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-accrual: # of loans | loan	62	56
Non-accrual, Amount | $	$ 24,304	$ 24,177
Residential And Consumer
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-accrual: # of loans | loan	500	406
Non-accrual, Amount | $	$ 91,122	$ 84,182

Loans Receivable, Net (Loans In

Loans Receivable, Net (Loans Individually Evaluated for Impairment by Class of Loans) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Recorded Investment
With an allowance recorded		$ 0
Total	$ 56,987	60,499
Unpaid Principal Balance
With an allowance recorded		0
Total	76,738	74,521
Related Allowance	4,191	2,139
Average Recorded Investment
With an allowance recorded		0
Total	58,184	63,655
Interest Income Recognized
With an allowance recorded		0
Total	2,814	2,525
Multi- Family Loans
Recorded Investment
With no related allowance	3,219	4,111
With an allowance recorded	0	0
Total	3,219	4,111
Unpaid Principal Balance
With no related allowance	6,806	7,846
With an allowance recorded	0	0
Total	6,806	7,846
Related Allowance	0	0
Average Recorded Investment
With no related allowance	2,871	4,746
With an allowance recorded	0	0
Total	2,872	4,746
Interest Income Recognized
With no related allowance	119	135
With an allowance recorded	0	0
Total	119	135
Commercial Real Estate Loans
Recorded Investment
With no related allowance	18,941	19,901
With an allowance recorded	0	3,094
Total	18,941	22,995
Unpaid Principal Balance
With no related allowance	27,961	23,601
With an allowance recorded	0	4,760
Total	27,961	28,361
Related Allowance	0	274
Average Recorded Investment
With no related allowance	19,025	17,056
With an allowance recorded	0	3,106
Total	19,025	20,162
Interest Income Recognized
With no related allowance	1,136	879
With an allowance recorded	0	72
Total	1,136	951
Commercial and Industrial Loans
Recorded Investment
With no related allowance	5,155	3,310
With an allowance recorded	4,240
Total	9,395	3,310
Unpaid Principal Balance
With no related allowance	5,160	3,310
With an allowance recorded	4,271
Total	9,431	3,310
Related Allowance	2,409	0
Average Recorded Investment
With no related allowance	3,575	1,985
With an allowance recorded	4,389
Total	7,964	1,985
Interest Income Recognized
With no related allowance	200	152
With an allowance recorded	194
Total	394	152
Construction Loans
Recorded Investment
With no related allowance	2,504	6,798
With an allowance recorded	0	0
Total	2,504	6,798
Unpaid Principal Balance
With no related allowance	6,412	9,292
With an allowance recorded	0	0
Total	6,412	9,292
Related Allowance	0	0
Average Recorded Investment
With no related allowance	4,288	13,609
With an allowance recorded	0	0
Total	4,288	13,609
Interest Income Recognized
With no related allowance	226	410
With an allowance recorded	0	0
Total	226	410
Commercial Loan
Recorded Investment
With no related allowance	29,819	34,120
With an allowance recorded	4,240	3,094
Total	34,059	37,214
Unpaid Principal Balance
With no related allowance	46,339	44,049
With an allowance recorded	4,271	4,760
Total	50,610	48,809
Related Allowance	2,409	274
Average Recorded Investment
With no related allowance	29,759	37,396
With an allowance recorded	4,389	3,106
Total	34,149	40,502
Interest Income Recognized
With no related allowance	1,681	1,576
With an allowance recorded	194	72
Total	1,875	1,648
Residential Mortgage Loans
Recorded Investment
With no related allowance	8,020	6,755
With an allowance recorded	14,908	16,530
Total	22,928	23,285
Unpaid Principal Balance
With no related allowance	12,433	8,830
With an allowance recorded	13,695	16,882
Total	26,128	25,712
Related Allowance	1,782	1,865
Average Recorded Investment
With no related allowance	7,611	6,606
With an allowance recorded	16,424	16,547
Total	24,035	23,153
Interest Income Recognized
With no related allowance	463	370
With an allowance recorded	476	507
Total	$ 939	$ 877

Loans Receivable, Net (Troubled

Loans Receivable, Net (Troubled Debt Restructured Loans) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2015USD ($)loan	Dec. 31, 2014USD ($)loan	Dec. 31, 2013USD ($)
Financing Receivable, Modifications [Line Items]
Accrual, number of loans | loan	39	55
Accrual, amount	$ 22,489	$ 35,624
Non-accrual, number of loans | loan	65	30
Non-accrual, amount	$ 24,950	$ 11,653
Troubled debt restructured, number of loans | loan	104	85
Troubled debt restructuring, Amount	$ 47,439	$ 47,277
Transfer of loans to loans held for sale	$ 347,955	$ 32,411	$ 0
Multi- Family Loans
Financing Receivable, Modifications [Line Items]
Accrual, number of loans | loan	0	2
Accrual, amount	$ 0	$ 1,122
Non-accrual, number of loans | loan	2	0
Non-accrual, amount	$ 1,580	$ 0
Troubled debt restructured, number of loans | loan	2	2
Troubled debt restructuring, Amount	$ 1,580	$ 1,122
Commercial Real Estate Loans
Financing Receivable, Modifications [Line Items]
Accrual, number of loans | loan	5	8
Accrual, amount	$ 13,161	$ 15,250
Non-accrual, number of loans | loan	9	1
Non-accrual, amount	$ 5,826	$ 3,197
Troubled debt restructured, number of loans | loan	14	9
Troubled debt restructuring, Amount	$ 18,987	$ 18,447
Commercial and Industrial Loans
Financing Receivable, Modifications [Line Items]
Accrual, number of loans | loan	1	2
Accrual, amount	$ 640	$ 1,381
Non-accrual, number of loans | loan	3	0
Non-accrual, amount	$ 2,586	$ 0
Troubled debt restructured, number of loans | loan	4	2
Troubled debt restructuring, Amount	$ 3,226	$ 1,381
Construction Loans
Financing Receivable, Modifications [Line Items]
Accrual, number of loans | loan	1	2
Accrual, amount	$ 313	$ 3,066
Non-accrual, number of loans | loan	2	0
Non-accrual, amount	$ 405	$ 0
Troubled debt restructured, number of loans | loan	3	2
Troubled debt restructuring, Amount	$ 718	$ 3,066
Commercial Loan
Financing Receivable, Modifications [Line Items]
Accrual, number of loans | loan	7	14
Accrual, amount	$ 14,114	$ 20,819
Non-accrual, number of loans | loan	16	1
Non-accrual, amount	$ 10,397	$ 3,197
Troubled debt restructured, number of loans | loan	23	15
Troubled debt restructuring, Amount	$ 24,511	$ 24,016
Residential Mortgage Loans
Financing Receivable, Modifications [Line Items]
Accrual, number of loans | loan	32	41
Accrual, amount	$ 8,375	$ 14,805
Non-accrual, number of loans | loan	49	29
Non-accrual, amount	$ 14,553	$ 8,456
Troubled debt restructured, number of loans | loan	81	70
Troubled debt restructuring, Amount	$ 22,928	$ 23,261

Loans Receivable, Net (Schedu66

Loans Receivable, Net (Schedule Of Troubled Debt Restructurings) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2015USD ($)loan	Dec. 31, 2014USD ($)loan
Financing Receivable, Allowance for Credit Losses [Line Items]
Number of Loans | loan	0	0
Pre-modification Interest Yield	4.97%	0.00%
Post- modification Interest Yield	4.97%	0.00%
Multi- Family Loans
Financing Receivable, Allowance for Credit Losses [Line Items]
Number of Loans | loan	1	0
Pre- modification Recorded Investment | $	$ 1,115	$ 0
Post- modification Recorded Investment | $	$ 1,115	$ 0
Number of Loans | loan	1	0
Pre-modification Interest Yield	3.88%	0.00%
Post- modification Interest Yield	3.88%	0.00%
Commercial Real Estate Loans
Financing Receivable, Allowance for Credit Losses [Line Items]
Number of Loans | loan	4	3
Pre- modification Recorded Investment | $	$ 824	$ 10,657
Post- modification Recorded Investment | $	$ 824	$ 7,657
Number of Loans | loan	4	3
Pre-modification Interest Yield	4.53%	6.59%
Post- modification Interest Yield	5.35%	5.75%
Construction Loans
Financing Receivable, Allowance for Credit Losses [Line Items]
Number of Loans | loan	2	0
Pre- modification Recorded Investment | $	$ 1,508	$ 0
Post- modification Recorded Investment | $	$ 1,508	$ 0
Commercial and Industrial Loans
Financing Receivable, Allowance for Credit Losses [Line Items]
Number of Loans | loan	2	0
Pre- modification Recorded Investment | $	$ 2,246	$ 0
Post- modification Recorded Investment | $	$ 2,246	$ 0
Number of Loans | loan	2	0
Pre-modification Interest Yield	6.24%	0.00%
Post- modification Interest Yield	6.24%	0.00%
Residential Mortgage Loans
Financing Receivable, Allowance for Credit Losses [Line Items]
Number of Loans | loan	19	11
Pre- modification Recorded Investment | $	$ 3,413	$ 3,217
Post- modification Recorded Investment | $	$ 3,413	$ 3,217
Number of Loans | loan	19	11
Pre-modification Interest Yield	4.84%	5.35%
Post- modification Interest Yield	3.40%	3.90%

Office Properties and Equipme67

Office Properties and Equipment, Net (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Property, Plant and Equipment [Line Items]
Office properties and equipment, gross	$ 277,470	$ 253,068
Less accumulated depreciation and amortization	104,951	92,169
Office properties and equipment, net	172,519	160,899
Depreciation and amortization expense	13,930	13,151	$ 8,540
Land
Property, Plant and Equipment [Line Items]
Office properties and equipment, gross	20,569	21,862
Office buildings
Property, Plant and Equipment [Line Items]
Office properties and equipment, gross	87,832	78,808
Leasehold improvements
Property, Plant and Equipment [Line Items]
Office properties and equipment, gross	79,898	66,857
Furniture, fixtures and equipment
Property, Plant and Equipment [Line Items]
Office properties and equipment, gross	77,096	68,420
Construction in process
Property, Plant and Equipment [Line Items]
Office properties and equipment, gross	$ 12,075	$ 17,121

Goodwill and Intangibles Asse68

Goodwill and Intangibles Assets Summary of Other Intangible Assets(Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Finite-Lived Intangible Assets [Line Items]
Gross Intangible Asset	$ 48,769	$ 49,283
Accumulated Amortization	(20,908)	(20,028)
Valuation Allowance	(121)	(121)
Net Intangible Assets	27,740	29,134
Goodwill	77,571	77,571
Goodwill and intangible assets	105,311	106,705
Mortgage Servicing Rights
Finite-Lived Intangible Assets [Line Items]
Gross Intangible Asset	23,411	23,925
Accumulated Amortization	(7,042)	(9,543)
Valuation Allowance	(121)	(121)
Net Intangible Assets	16,248	14,261
Core Deposit Premium
Finite-Lived Intangible Assets [Line Items]
Gross Intangible Asset	25,058	25,058
Accumulated Amortization	(13,726)	(10,375)
Valuation Allowance	0	0
Net Intangible Assets	11,332	14,683
Other
Finite-Lived Intangible Assets [Line Items]
Gross Intangible Asset	300	300
Accumulated Amortization	(140)	(110)
Valuation Allowance	0	0
Net Intangible Assets	$ 160	$ 190

Goodwill and Intangibles Asse69

Goodwill and Intangibles Assets Estimated Future Amortization (Details) $ in Thousands	Dec. 31, 2015USD ($)
Mortgage Servicing Rights
Finite-Lived Intangible Assets [Line Items]
2,016	$ 473
2,017	506
2,018	522
2,019	538
2,020	552
Core Deposit Premium
Finite-Lived Intangible Assets [Line Items]
2,016	2,900
2,017	2,441
2,018	1,983
2,019	1,524
2,020	1,109
Other
Finite-Lived Intangible Assets [Line Items]
2,016	30
2,017	30
2,018	30
2,019	30
2,020	$ 30

Goodwill and Intangibles Asse70

Goodwill and Intangibles Assets Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Finite-Lived Intangible Assets [Line Items]
Loans sold	$ 2,120	$ 1,590
Estimated fair value of servicing asset in intangible assets	$ 16.2	$ 14.3
Weighted average discount rate of servicing assets	10.20%
Weighted average constant prepayment rate on mortgages	10.80%
Weighted average life of servicing assets, years	6 years 1 month
Core Deposit Premium
Finite-Lived Intangible Assets [Line Items]
Useful life		10 years
Core Deposit Premium | Roma Financial Corporation
Finite-Lived Intangible Assets [Line Items]
Acquired intangibles		$ 1.9

Deposits (Summary of Deposits)

Deposits (Summary of Deposits) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Banking and Thrift [Abstract]
Checking accounts, Weighted Average Rate	0.17%	0.20%
Money market deposits, Weighted Average Rate	0.67%	0.71%
Savings, Weighted Average Rate	0.29%	0.27%
Total transaction accounts, Weighted Average Rate	0.38%	0.40%
Certificates of deposit, Weighted Average Rate	1.14%	1.00%
Total deposits, Weighted Average Rate	0.56%	0.53%
Checking account, Amount	$ 4,636,025	$ 3,892,839
Money market deposits, Amount	3,861,317	3,390,238
Savings, Amount	2,150,004	2,318,911
Total transaction accounts, Amount	10,647,346	9,601,988
Certificates of deposit, Amount	3,416,310	2,570,338
Total Deposit, Amount	$ 14,063,656	$ 12,172,326
Checking accounts, Percentage of Total	32.96%	31.98%
Money market deposit, Percentage of Total	27.46%	27.85%
Savings, Percentage of Total	15.29%	19.05%
Total transaction accounts, Percentage of Total	75.71%	78.88%
Certificate of deposit, Percentage of Total	24.29%	21.12%
Total Deposits, Percentage of Total	100.00%	100.00%

Deposits (Scheduled Maturities

Deposits (Scheduled Maturities of Certificates of Deposit) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Banking and Thrift [Abstract]
Within one year	$ 2,586,076	$ 1,450,655
One to two years	496,288	660,523
Two to three years	167,028	278,190
Three to four years	57,443	74,526
After four years	109,475	106,444
Deposits, Domestic	3,416,310	2,570,338
Certificates of deposit, $100,000 or More, Total	$ 1,320,000	$ 1,190,000

Deposits (Interest Expense on D

Deposits (Interest Expense on Deposits) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Banking and Thrift [Abstract]
Checking accounts	$ 9,642	$ 8,755	$ 6,245
Money market deposits	23,562	13,664	7,537
Savings	6,976	6,639	6,320
Certificates of deposit	31,234	30,148	29,867
Interest expense of deposits	$ 71,414	$ 59,206	$ 49,969

Borrowed Funds (Narrative) (Det

Borrowed Funds (Narrative) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Debt Instrument [Line Items]
Maximum month end balance of repurchase agreements	$ 163,000,000	$ 261,200,000	$ 267,700,000
Average amount of repurchase agreements outstanding during the years	$ 159,400,000	$ 192,900,000	$ 165,400,000
Repurchase agreements, average interest rate	2.25%	2.02%	1.50%
FHLB, borrowing capacity	$ 8,780,000,000
FHLB, borrowing capacity outstanding	3,120,000,000
Letters of credit outstanding	$ 1,830,000,000
Minimum
Debt Instrument [Line Items]
Federal funds rate, basis spread	0.20%
Maximum
Debt Instrument [Line Items]
Federal funds rate, basis spread	0.30%
Unsecured Debt
Debt Instrument [Line Items]
Commitment for overnight with other institutions	$ 125,000,000

Borrowed Funds (Summary of Borr

Borrowed Funds (Summary of Borrowed Funds) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Summary Of Borrowed Funds [Line Items]
Funds borrowed under repurchase agreements, Principal	$ 156,307	$ 167,918
Funds borrowed under repurchase agreements, Weighted Average Rage	2.21%	2.28%
FHLB advances, Principal	$ 3,106,783	$ 2,598,186
FHLB advances, Weighted Average Rate	2.12%	2.24%
Total borrowed funds, Principal	$ 3,263,090	$ 2,766,104
Total borrowed funds, Weighted Average Rate	2.13%	2.24%
Other Brokers [Member]
Summary Of Borrowed Funds [Line Items]
Funds borrowed under repurchase agreements, Principal	$ 131,924	$ 142,847
Funds borrowed under repurchase agreements, Weighted Average Rage	1.89%	2.00%
Federal Home Loan Bank [Member]
Summary Of Borrowed Funds [Line Items]
Funds borrowed under repurchase agreements, Principal	$ 24,383	$ 25,071
Funds borrowed under repurchase agreements, Weighted Average Rage	3.90%	3.90%

Borrowed Funds (Borrowed Funds

Borrowed Funds (Borrowed Funds Scheduled Maturities) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Debt Disclosure [Abstract]
Within one year, Principal	$ 500,000	$ 576,250
One to two years, Principal	249,383	325,000
Two to three years, Principal	862,924	250,071
Three to four years, Principal	469,782	763,597
Four to five years, Principal	650,000	444,994
After five years, Principal	531,001	406,192
Total borrowed funds, Principal	$ 3,263,090	$ 2,766,104
Within one year, Weighted Average Rate	1.99%	2.03%
One to two years, Weighted Average Rate	3.00%	2.79%
Two to three years, Weighted Average Rate	2.13%	3.00%
Three to four years, Weighted Average Rate	1.78%	2.22%
Four to five years, Weighted Average Rate	1.99%	1.78%
After five years, Weighted Average Rate	2.30%	2.18%
Total borrowed funds, Weighted Average Rate	2.13%	2.24%

Borrowed Funds (Amortized Cost

Borrowed Funds (Amortized Cost and Fair Value of The Underlying Securities Used As Collateral For Securities Sold Under Agreements to Repurchase) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Schedule of Trading Securities and Other Trading Assets [Line Items]
Amortized cost of collateral	$ 475,984	$ 195,890
Fair value of collateral	481,401	198,502
Mortgage-Based Securities [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Amortized cost of collateral	475,984	195,890
Fair value of collateral	$ 481,401	$ 198,502

Income Taxes (Narrative) (Detai

Income Taxes (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Statutory federal income tax rate	35.00%
Noncash Contribution Expense	$ 0	$ 20,000	$ 0
Contribution in stock to charitable foundation	0	10,000	$ 0
Deferred Tax Assets, Valuation Allowance	346	$ 346
Retained earnings without deferred income taxes	45,200
Deferred income taxes	$ 19,200

Income Taxes (Summary of Compon

Income Taxes (Summary of Components of Income Tax Expense (Benefit)) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Current tax expense, Federal									$ 87,748	$ 77,029	$ 76,692
Current tax expense, State									14,804	7,508	7,881
Current tax expense, Total									102,552	84,537	84,573
Deferred tax (benefit) expense, Federal									4,310	(3,846)	(16,887)
Deferred tax (benefit) expense, State									(7,490)	(5,940)	(3,931)
Deferred tax (benefit) expense, Total									(3,180)	(9,786)	(20,818)
Total income tax expense (benefit)	$ 24,448	$ 22,865	$ 26,939	$ 25,120	$ 21,547	$ 23,092	$ 9,596	$ 20,516	$ 99,372	$ 74,751	$ 63,755

Income Taxes (Summary of Reconc

Income Taxes (Summary of Reconciliation Between the Actual Income Tax Expense (Benefit) And The 'Expected' Amount Computed Using Applicable Statutory Federal Income Tax Rate) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
“Expected” federal income tax expense									$ 98,307	$ 72,265	$ 61,525
State tax, net									4,753	1,019	2,567
Bank owned life insurance									(1,382)	(1,628)	(1,014)
Expiration of loss carryforward									0	0	645
Change in valuation allowance for federal deferred tax assets									0	0	(645)
Acquisition related net operating loss									(4,076)	0	0
ESOP fair market value adjustment									947	349	538
Non-deductible compensation									276	3,334	411
Non-deductible acquisition related expenses									0	0	297
Expiration of stock options									19	2	0
Other									528	(590)	(569)
Total income tax expense (benefit)	$ 24,448	$ 22,865	$ 26,939	$ 25,120	$ 21,547	$ 23,092	$ 9,596	$ 20,516	$ 99,372	$ 74,751	$ 63,755

Income Taxes (Summary of Deferr

Income Taxes (Summary of Deferred Tax Asset and Liability in Temporary Differences And Loss Carryforwards) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Employee benefits	$ 36,372	$ 30,832
Deferred compensation	1,417	1,332
Premises and equipment	2,262	1,532
Allowance for loan losses	88,894	79,255
Net unrealized loss on securities	10,420	9,101
Net other than temporary impairment loss on securities	42,085	44,225
ESOP	3,695	2,921
Allowance for delinquent interest	13,071	12,379
Fair value adjustments related to acquisitions	31,986	38,309
Charitable contribution carryforward	5,823	5,685
Loan origination costs	7,127	10,821
Intangible assets	45	0
Other	1,409	1,969
Gross deferred tax asset	244,606	238,361
Valuation allowance	(346)	(346)
Net deferred tax asset	244,260	238,015
Intangible assets	0	251
Mortgage servicing rights	6,893	5,866
Gross deferred tax liability	6,893	6,117
Net deferred tax asset	$ 237,367	$ 231,898

Benefit Plans (Narrative) (Deta

Benefit Plans (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands	Jun. 23, 2015	May. 07, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Oct. 31, 2005
Defined Benefit Plan Disclosure [Line Items]
Funded status			$ (47,887)	$ (40,522)
Accumulated benefit obligation			$ 28,600	23,600
Matching contribution			50.00%
Contribution by participants, percentage			6.00%
Company's aggregate contributions			$ 2,200	$ 2,000	$ 1,500
Weighted average grant date fair value of options granted (per share)			$ 0.0312	$ 0.0363
Number of stock option grated due to Roma Acquisition			11,576,611
Weighted average exercise price for options grated due to Roma Acquisition, per share			$ 12.54
Future expense of non vested option outstanding			$ 32,717
Expected future compensation expense relating to unvested restricted shares			5 years 8 months 27 days
Employee Stock Ownership Plan
Defined Benefit Plan Disclosure [Line Items]
Shares authorized to purchase						10,847,883
Share price		$ 10				$ 3.92
Investors bank employee stock ownership plan (shares)		6,617,421
Outstanding loan principle balance		$ 33,900	$ 94,900
ESOP, Incremental borrowing, amount		$ 66,200
Shares allocated to participants			4,201,759
Shares unallocated or not yet committed to be released			13,263,545
Fair market value			$ 165,000
Compensation expense			5,500	$ 5,100	3,000
Amended And Restated Supplemental Esop And Retirement Plan
Defined Benefit Plan Disclosure [Line Items]
Compensation expense			$ 656	$ 568	782
Pentegra DB Plan
Defined Benefit Plan Disclosure [Line Items]
Funded status			99.17%	107.60%
Contribution and pension cost			$ 9,200	$ 5,300	$ 5,900
Accrued liability in pension plan			$ 727	$ 672
Defined benefit plan maximum employer contribution, less than			5.00%
Expected contribution for next year			$ 6,500
Employee Stock Option
Defined Benefit Plan Disclosure [Line Items]
Issuance of additional restricted stock				144,177	504,696
Restricted Stock
Defined Benefit Plan Disclosure [Line Items]
Options granted (shares)			6,849,832
Issuance of additional restricted stock				38,250	7,650
Future expense of non vested option outstanding			$ 77,600
Expected future compensation expense relating to unvested restricted shares			5 years 7 months 28 days
Roma Financial Corporation
Defined Benefit Plan Disclosure [Line Items]
Number of stock option grated due to Roma Acquisition					1,584,235
Weighted average exercise price for options grated due to Roma Acquisition, per share					$ 6.11
2015 Equity Incentive Plan
Defined Benefit Plan Disclosure [Line Items]
Shares authorized to purchase	30,881,296
Options granted (shares)	6,849,832
Weighted average grant date fair value of options granted (per share)			$ 3.12
2015 Equity Incentive Plan | Employee Stock Option
Defined Benefit Plan Disclosure [Line Items]
Shares authorized to purchase	17,646,455
Contractual term of option	10 years
2015 Equity Incentive Plan | Restricted Stock
Defined Benefit Plan Disclosure [Line Items]
Shares authorized to purchase	13,234,841
Options granted (shares)	11,576,612
Minimum | 2015 Equity Incentive Plan
Defined Benefit Plan Disclosure [Line Items]
Vesting period	5 years
Maximum | 2015 Equity Incentive Plan
Defined Benefit Plan Disclosure [Line Items]
Vesting period	7 years

Benefit Plans (Schedule of Info

Benefit Plans (Schedule of Information Regarding Supplemental Executive Retirement Wage Replacement Plan And The Directors' Defined Benefit Plan) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation at beginning of year	$ 40,522	$ 29,152
Service cost	3,096	2,319	$ 1,799
Interest cost	1,497	1,322	908
(Gain) loss due to change in mortality assumption	(778)	3,289
(Gain) loss due to change in discount rate	(1,587)	4,816
Loss due to demographic changes	6,008	495
Benefits paid	(871)	(871)
Benefit obligation at end of year	47,887	40,522	$ 29,152
Funded status	$ (47,887)	$ (40,522)

Benefit Plans (Components of Ac

Benefit Plans (Components of Accumulated Other Comprehensive Loss Related To Pension Plans On A Pre-Tax Basis) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Compensation and Retirement Disclosure [Abstract]
Prior service cost	$ 0	$ 49
Net actuarial gain	19,284	16,923
Total amounts recognized in accumulated other comprehensive income	$ 19,284	$ 16,972

Benefit Plans (Schedule of Weig

Benefit Plans (Schedule of Weighted-Average Actuarial Assumptions Used) (Details)	Dec. 31, 2015	Dec. 31, 2014
Compensation and Retirement Disclosure [Abstract]
Discount rate	3.99%	3.71%
Rate of compensation increase	4.36%	4.19%

Benefit Plans (Components of Ne

Benefit Plans (Components of Net Periodic Benefit Cost) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Compensation and Retirement Disclosure [Abstract]
Service cost	$ 3,096	$ 2,319	$ 1,799
Interest cost	1,497	1,322	908
Amortization of prior service cost	49	98	98
Amortization of net loss	1,282	633	660
Total net periodic benefit cost	$ 5,924	$ 4,372	$ 3,465

Benefit Plans (Weighted Average

Benefit Plans (Weighted Average Assumptions Used to Determine Net Periodic Benefit Cost) (Details)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Compensation and Retirement Disclosure [Abstract]
Discount rate	3.71%	4.53%	3.56%
Rate of compensation increase	4.19%	4.00%	3.87%

Benefit Plans (Estimated Future

Benefit Plans (Estimated Future Benefit Payments) (Details) $ in Thousands	Dec. 31, 2015USD ($)
Compensation and Retirement Disclosure [Abstract]
2,016	$ 1,175
2,017	925
2,018	906
2,019	885
2,020	2,882
2021 through 2026	$ 22,174

Benefit Plans (Weighted Avera89

Benefit Plans (Weighted Average Assumptions) (Details) - $ / shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average expected life (in years)	7 years 5 months	6 years 6 months	6 years 6 months
Weighted average risk-free rate of return (in percentage)	1.96%	1.69%	1.38%
Dividend yield (in percentage)	1.59%	0.35%	0.16%
Weighted average fair value of options granted (per share)	$ 0.0312	$ 0.0363
Expected volatility (in percentage)	25.33%	32.97%	33.20%
2015 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average expected life (in years)	7 years 5 months 5 days
Weighted average risk-free rate of return (in percentage)	1.96%
Weighted average volatility (in percentage)	25.33%
Dividend yield (in percentage)	1.59%
Weighted average fair value of options granted (per share)	$ 3.12

Benefit Plans (Summary of Non-V

Benefit Plans (Summary of Non-Vested Options and Restricted Shares) (Details) - Restricted Stock	12 Months Ended
	Dec. 31, 2015$ / sharesshares
Number of Shares Awarded
Number of Shares Awarded, Non-vested Beginning Balance | shares	0
Number of Shares Awarded, Granted | shares	6,849,832
Number of Shares Awarded, Vested | shares	0
Number of Shares, Awarded, Forfeited | shares	(90,000)
Number of Shares Awarded, Non-vested Ending Balance | shares	6,759,832
Weighted Average Grant Date Fair Value
Weighted Average Grant Date Fair Value, Non-vested Beginning Balance | $ / shares	$ 0
Weighted Average Grant Date Fair Value, Granted | $ / shares	12.54
Weighted Average Grant Date Fair Value, Vested | $ / shares	0
Weighted Average Grant Date Fair Value, Forfeited | $ / shares	12.54
Weighted Average Grant Date Fair Value, Non-vested Ending Balance | $ / shares	$ 12.64

Benefit Plans (Summary of Stock

Benefit Plans (Summary of Stock Option Activity and Related Information) (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Number of Stock Options, Outstanding Beginning Balance	9,092,584
Number of Stock Options, Granted	11,576,611
Number of Stock Options, Exercised	(1,698,283)
Number of Stock Options, Forfeited	(161,419)
Number of Stock Options, Expired	(4,677)
Number of Stock Options, Outstanding Ending Balance	18,804,816	9,092,584
Number of Stock Options, Exercisable Ending Balance	7,366,289
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract]
Weighted Average Exercise Price, Outstanding Beginning Balance	$ 6.06
Weighted Average Exercise Price, Granted	12.54
Weighted Average Exercise Price, Exercised	5.96
Weighted Average Exercise Price, Forfeited	12.41
Weighted Average Exercise Price, Expired	9.90
Weighted Average Exercise Price, Outstanding Ending Balance	10	$ 6.06
Weighted Average Exercise Price, Exercisable Ending Balance	$ 6.06
Outstanding, Weighted Average Remaining Contractual Life	6 years 9 months 11 days	2 years 9 months 18 days
Granted, Weighted Average Remaining Contractual Life		9 years 11 months 12 days
Exercised, Weighted Average Remaining Contractual Life	1 year 7 months 6 days
Weighted Average Remaining Contractual Life, Exercisable Ending Balance	1 year 10 months 2 days
Aggregate Intrinsic Value, Outstanding Beginning Balance	$ 46,984
Aggregate Intrinsic Value, Outstanding Ending Balance	46,996	$ 46,984
Aggregate Intrinsic Value, Exercisable at Ending Balance	$ 46,975

Benefit Plans (Share-based comp

Benefit Plans (Share-based compensation) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock option expense	$ 2,905	$ 1,800	$ 365
Restricted stock expense	6,314	11,900	3,100
Total share based compensation expense	$ 9,219	$ 13,700	$ 3,465

Commitments and Contingencies93

Commitments and Contingencies (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Rental expense	$ 19,200	$ 17,300	$ 15,200
Loans receivable, net	$ 16,661,133	14,887,570
Standby letters of credit extended for a term, years	1 year
Letters of credit outstanding	$ 1,830,000
Commercial Real Estate Loans
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Commitments to fixed- and variable-rate loans	566,900
Commitments To Originate Fixed
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Commitments to fixed- and variable-rate loans	57,400
Commitments To Purchase Fixed
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Commitments to fixed- and variable-rate loans	82,700
Unused lines of Credit
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Commitment	960,500
Commitments To Fund Loans
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Commitment	26,500
Commitments To Sell Loans
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Commitment	19,000
Standby Letters of Credit
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Letters of credit outstanding	23,700
Commercial Loan
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Letters of credit outstanding	600
One to Four Family Mortgage Loans
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Loans receivable, net	$ 172,300	$ 288,000

Commitments and Contingencies94

Commitments and Contingencies (Projected Annual Minimum Rental Commitments) (Details) $ in Thousands	Dec. 31, 2015USD ($)
Commitments and Contingencies Disclosure [Abstract]
2,016	$ 20,310
2,017	20,055
2,018	19,190
2,019	18,588
2,020	17,013
Thereafter	120,877
Projected annual minimum rental commitments	$ 216,033

Fair Value Measurements (Narrat

Fair Value Measurements (Narrative) (Details)	12 Months Ended
	Dec. 31, 2015USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Outstanding minimum balance of loans that are evaluated for impairment individually	$ 1,000,000
Mortgage Servicing Rights
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Discount rate	10.20%
Mortgage Servicing Rights | Maximum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Prepayment range	26.28%
Mortgage Servicing Rights | Minimum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Prepayment range	6.30%
Loans Receivable
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Outstanding minimum balance of loans to be evaluated for impairment individually	$ 1,000,000
Loans Receivable | Maximum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Discount rate	25.00%
Loans Receivable | Minimum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Discount rate	0.00%
Other Real Estate Owned | Maximum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Discount rate	25.00%
Other Real Estate Owned | Minimum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Discount rate	0.00%

Fair Value Measurements (Carryi

Fair Value Measurements (Carrying Value of Our Assets Measured at Fair Value on a Recurring Basis) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated fair value	$ 1,304,697	$ 1,197,924
Equity Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated fair value	6,495	8,523
Mortgage-backed securities:
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated fair value	1,298,202	1,189,401
Federal Home Loan Mortgage Corporation
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated fair value	547,451	507,283
Federal National Mortgage Association
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated fair value	726,072	681,992
Government National Mortgage Association
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated fair value	24,679	126
Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated fair value	1,304,697	1,197,924
Fair Value, Measurements, Recurring | Equity Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated fair value	6,495	8,523
Fair Value, Measurements, Recurring | Mortgage-backed securities:
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated fair value	1,298,202	1,189,401
Fair Value, Measurements, Recurring | Federal Home Loan Mortgage Corporation
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated fair value	547,451	507,283
Fair Value, Measurements, Recurring | Federal National Mortgage Association
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated fair value	726,072	681,992
Fair Value, Measurements, Recurring | Government National Mortgage Association
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated fair value	24,679	126
Level 1 | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated fair value	6,495	6,082
Level 1 | Fair Value, Measurements, Recurring | Equity Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated fair value	6,495	6,082
Level 1 | Fair Value, Measurements, Recurring | Mortgage-backed securities:
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated fair value	0	0
Level 1 | Fair Value, Measurements, Recurring | Federal Home Loan Mortgage Corporation
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated fair value	0	0
Level 1 | Fair Value, Measurements, Recurring | Federal National Mortgage Association
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated fair value	0	0
Level 1 | Fair Value, Measurements, Recurring | Government National Mortgage Association
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated fair value	0	0
Level 2 | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated fair value	1,298,202	1,191,842
Level 2 | Fair Value, Measurements, Recurring | Equity Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated fair value	0	2,441
Level 2 | Fair Value, Measurements, Recurring | Mortgage-backed securities:
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated fair value	1,298,202	1,189,401
Level 2 | Fair Value, Measurements, Recurring | Federal Home Loan Mortgage Corporation
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated fair value	547,451	507,283
Level 2 | Fair Value, Measurements, Recurring | Federal National Mortgage Association
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated fair value	726,072	681,992
Level 2 | Fair Value, Measurements, Recurring | Government National Mortgage Association
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated fair value	24,679	126
Level 3 | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated fair value	0	0
Level 3 | Fair Value, Measurements, Recurring | Equity Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated fair value	0	0
Level 3 | Fair Value, Measurements, Recurring | Mortgage-backed securities:
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated fair value	0	0
Level 3 | Fair Value, Measurements, Recurring | Federal Home Loan Mortgage Corporation
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated fair value	0	0
Level 3 | Fair Value, Measurements, Recurring | Federal National Mortgage Association
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated fair value	0	0
Level 3 | Fair Value, Measurements, Recurring | Government National Mortgage Association
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated fair value	$ 0	$ 0

Fair Value Measurements (Change

Fair Value Measurements (Changes in Level 3 Assets Measured at Fair Value on Recurring Basis) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Beginning balance	$ 0	$ 670
Net income	0	470
Other comprehensive income (loss)	0	(229)
Sales	0	(911)
Settlements	0	0
Ending balance	$ 0	$ 0

Fair Value Measurements (Carr98

Fair Value Measurements (Carrying Value of Our Assets Measured at Fair Value on a Non-Recurring Basis) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
MSR, net	$ 16,200	$ 14,300
Fair Value, Measurements, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
MSR, net		13,081
Other real estate owned	510	566
Total	510	13,647
Fair Value, Measurements, Nonrecurring [Member] | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other real estate owned	0	0
Total	0	0
Fair Value, Measurements, Nonrecurring [Member] | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other real estate owned	0	0
Total	0	0
Fair Value, Measurements, Nonrecurring [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
MSR, net		13,081
Other real estate owned	510	566
Total	$ 510	$ 13,647
Other Real Estate Owned | Minimum
Fair Value Inputs [Abstract]
Lack of marketability, range	0.00%	0.00%
Other Real Estate Owned | Maximum
Fair Value Inputs [Abstract]
Lack of marketability, range	25.00%	25.00%
Other Real Estate Owned | Weighted Average
Fair Value Inputs [Abstract]
Lack of marketability, range	8.90%	15.87%
Mortgage Servicing Rights | Minimum
Fair Value Inputs [Abstract]
Prepayment speeds, range		5.70%
Mortgage Servicing Rights | Maximum
Fair Value Inputs [Abstract]
Prepayment speeds, range		29.40%
Mortgage Servicing Rights | Weighted Average
Fair Value Inputs [Abstract]
Prepayment speeds, range		11.22%

Fair Value Measurements (Carr99

Fair Value Measurements (Carrying Amounts and Estimated Fair Values) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Securities available-for-sale	$ 1,304,697	$ 1,197,924
Securities held-to-maturity	1,888,686	1,609,365
Estimated Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	148,904	230,961
Securities available-for-sale	1,304,697	1,197,924
Securities held-to-maturity	1,888,686	1,609,365
Stock in FHLB	178,437	151,287
Loans held for sale	7,431	6,868
Net loans	16,650,529	14,747,319
Deposits, other than time deposits	10,647,346	9,601,988
Time deposits	3,414,528	2,580,572
Borrowed funds	3,277,983	2,796,969
Carrying value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	148,904	230,961
Securities available-for-sale	1,304,697	1,197,924
Securities held-to-maturity	1,844,223	1,564,479
Stock in FHLB	178,437	151,287
Loans held for sale	7,431	6,868
Net loans	16,661,133	14,887,570
Deposits, other than time deposits	10,647,346	9,601,988
Time deposits	3,416,310	2,570,338
Borrowed funds	3,263,090	2,766,104
Level 1 | Estimated Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	148,904	230,961
Securities available-for-sale	6,495	6,082
Securities held-to-maturity	0	0
Stock in FHLB	178,437	151,287
Loans held for sale	0	0
Net loans	0	0
Deposits, other than time deposits	10,647,346	9,601,988
Time deposits	0	0
Borrowed funds	0	0
Level 2 | Estimated Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	0	0
Securities available-for-sale	1,298,202	1,191,842
Securities held-to-maturity	1,810,869	1,544,129
Stock in FHLB	0	0
Loans held for sale	7,431	6,868
Net loans	0	0
Deposits, other than time deposits	0	0
Time deposits	3,414,528	2,580,572
Borrowed funds	3,277,983	2,796,969
Level 3 | Estimated Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	0	0
Securities available-for-sale	0	0
Securities held-to-maturity	77,817	65,236
Stock in FHLB	0	0
Loans held for sale	0	0
Net loans	16,650,529	14,747,319
Deposits, other than time deposits	0	0
Time deposits	0	0
Borrowed funds	$ 0	$ 0

Regulatory Capital (Details)

Regulatory Capital (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Bank
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier I capital (to average assets) Actual, Amount	$ 2,558,334	$ 2,339,572
Tier I capital (to average assets) Actual, Ratio	12.41%	12.79%
Tier I capital (to average assets) For Capital Adequacy Purposes, Amount	$ 824,607	$ 731,884
Tier I capital (to average assets) For Capital Adequacy Purposes, Ratio	4.00%	4.00%
Tier I capital (to average assets) To be Well Capitalized Under Prompt Corrective Action Provisions, Amount	$ 1,030,759	$ 914,855
Tier I capital (to average assets) To be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	5.00%	5.00%
Tier One Common Equity	$ 2,558,334
Tier One Common Equity Leverage Capital to Average Assets	15.87%
Tier One Leverage Common Equity Capital Required for Capital Adequacy	$ 725,523
Tier One Risk Based Common Equity Leverage Capital Required for Capital Adequacy to Average Assets	4.50%
Tier One Common Equity Risk Based Capital Required to be Well Capitalized	$ 1,047,978
Tier One Common Equity Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets	6.50%
Tier I capital (to risk-weighted assets) Actual, Amount	$ 2,558,334	$ 2,339,572
Tier I capital (to risk-weighted assets) Actual, Ratio	15.87%	17.01%
Tier I capital (to risk-weighted assets) For Capital Adequacy Purposes, Amount	$ 967,364	$ 550,321
Tier I capital (to risk-weighted assets) For Capital Adequacy Purposes, Ratio	6.00%	4.00%
Tier I capital (to risk-weighted assets) To be Well Capitalized Under Prompt Corrective Action Provisions, Amount	$ 1,289,819	$ 825,481
Tier I capital (to risk-weighted assets) To be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	8.00%	6.00%
Total capital (to risk-weighted assets) Actual, Amount	$ 2,760,081	$ 2,511,897
Total capital (to risk-weighted assets) Actual, Ratio	17.12%	18.26%
Total capital (to risk-weighted assets) For Capital Adequacy Purposes, Amount	$ 1,289,819	$ 1,100,641
Total capital (to risk-weighted assets) For Capital Adequacy Purposes, Ratio	8.00%	8.00%
Total capital (to risk-weighted assets) To be Well Capitalized Under Prompt Corrective Action Provisions, Amount	$ 1,612,274	$ 1,375,802
Total capital (to risk-weighted assets) To be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	10.00%	10.00%
Company
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier I capital (to average assets) Actual, Amount	$ 3,259,928	$ 3,511,433
Tier I capital (to average assets) Actual, Ratio	15.80%	19.17%
Tier I capital (to average assets) For Capital Adequacy Purposes, Amount	$ 825,139	$ 732,710
Tier I capital (to average assets) For Capital Adequacy Purposes, Ratio	4.00%	4.00%
Tier One Common Equity	$ 3,259,928
Tier One Common Equity Leverage Capital to Average Assets	20.20%
Tier One Leverage Common Equity Capital Required for Capital Adequacy	$ 726,146
Tier One Risk Based Common Equity Leverage Capital Required for Capital Adequacy to Average Assets	4.50%
Tier I capital (to risk-weighted assets) Actual, Amount	$ 3,259,928	$ 3,511,433
Tier I capital (to risk-weighted assets) Actual, Ratio	20.20%	25.48%
Tier I capital (to risk-weighted assets) For Capital Adequacy Purposes, Amount	$ 968,194	$ 551,181
Tier I capital (to risk-weighted assets) For Capital Adequacy Purposes, Ratio	6.00%	4.00%
Total capital (to risk-weighted assets) Actual, Amount	$ 3,461,649	$ 3,684,024
Total capital (to risk-weighted assets) Actual, Ratio	21.45%	26.74%
Total capital (to risk-weighted assets) For Capital Adequacy Purposes, Amount	$ 1,290,926	$ 1,102,362
Total capital (to risk-weighted assets) For Capital Adequacy Purposes, Ratio	8.00%	8.00%

Parent Company Only Financia101

Parent Company Only Financial Statements (Balance Sheets) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Condensed Financial Statements, Captions [Line Items]
Securities available-for-sale, at estimated fair value	$ 1,304,697	$ 1,197,924
ESOP loan receivable	16,661,133	14,887,570
Other assets	4,664	10,333
Total assets	20,888,684	18,773,639
Total liabilities	17,577,037	15,195,784
Total stockholders' equity	3,311,647	3,577,855	$ 1,334,327	$ 1,066,817
Total liabilities and stockholders’ equity	20,888,684	18,773,639
Parent Company
Condensed Financial Statements, Captions [Line Items]
Cash and due from banks	569,513	1,022,231
Securities available-for-sale, at estimated fair value	1,733	3,791
Investment in subsidiary	2,611,080	2,409,557
ESOP loan receivable	94,889	96,951
Other assets	45,898	52,499
Total assets	3,323,113	3,585,029
Total liabilities	11,466	7,174
Total stockholders' equity	3,311,647	3,577,855
Total liabilities and stockholders’ equity	$ 3,323,113	$ 3,585,029

Parent Company Only Financia102

Parent Company Only Financial Statements (Statements of Operations) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Condensed Income Statements, Captions [Line Items]
Interest in ESOP loan receivable									$ 663,424	$ 603,438	$ 504,622
Total interest and dividend income	$ 188,138	$ 186,897	$ 181,529	$ 175,159	$ 171,090	$ 167,058	$ 164,089	$ 158,625	731,723	660,862	545,068
Interest expense	37,322	35,623	32,977	30,717	30,919	29,212	29,326	29,434	136,639	118,891	109,642
Other expenses									28,267	27,253	19,775
Income before income tax expense	68,850	71,659	73,301	67,067	64,622	62,134	24,781	54,935	280,877	206,472	175,786
Income tax expense	24,448	22,865	26,939	25,120	21,547	23,092	9,596	20,516	99,372	74,751	63,755
Net income	$ 44,402	$ 48,794	$ 46,362	$ 41,947	$ 43,075	$ 39,042	$ 15,185	$ 34,419	181,505	131,721	112,031
Parent Company
Condensed Income Statements, Captions [Line Items]
Interest in ESOP loan receivable									3,151	2,499	1,125
Dividend from subsidiary									0	0	10,000
Interest on deposit with subsidiary									2	2	2
Investment Income, Interest and Dividend									65	64	49
Income (loss) on securities transactions									1,682	145	89
Total interest and dividend income									4,900	2,710	11,265
Interest expense									54	43	53
Other expenses									3,170	12,197	1,420
Income before income tax expense									1,676	(9,530)	9,792
Income tax expense									540	(3,675)	233
Income before undistributed earnings of subsidiary									1,136	(5,855)	9,559
Equity in undistributed earnings of subsidiary									180,370	137,576	102,472
Net income									$ 181,506	$ 131,721	$ 112,031

Parent Company Only Financia103

Parent Company Only Financial Statements (Statement of Comprehensive Income) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Condensed Statement of Income Captions [Line Items]
Net income	$ 44,402	$ 48,794	$ 46,362	$ 41,947	$ 43,075	$ 39,042	$ 15,185	$ 34,419	$ 181,505	$ 131,721	$ 112,031
Unrealized gain on securities available-for-sale									(4,933)	5,952	(12,827)
Total other comprehensive (loss) income									(5,421)	3,292	(18,089)
Total comprehensive income									176,084	135,013	93,942
Parent Company
Condensed Statement of Income Captions [Line Items]
Net income									181,506	131,721	112,031
Unrealized gain on securities available-for-sale									433	1,482	1,316
Total other comprehensive (loss) income									433	1,482	1,316
Total comprehensive income									$ 181,939	$ 133,203	$ 113,347

Parent Company Only Financia104

Parent Company Only Financial Statements (Statements of Cash Flows) (Details) - USD ($) $ in Thousands	May. 07, 2014	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Condensed Cash Flow Statements, Captions [Line Items]
Net income		$ 44,402	$ 48,794	$ 46,362	$ 41,947	$ 43,075	$ 39,042	$ 15,185	$ 34,419	$ 181,505	$ 131,721	$ 112,031
Contribution in stock to charitable foundation										0	10,000	0
Decrease in other assets										4,245	4,425	(6,741)
Net cash provided by operating activities										533,134	277,388	176,094
Redemption of equity securities available-for-sale										0	164	108
Cash received from MHC for merger										0	11,307	0
Net cash used in investing activities										(2,585,122)	(2,936,744)	(1,261,322)
Proceeds from issuance of common stock	$ 2,150,000
Purchase of treasury stock										(382,922)	(13,523)	(1,531)
Net tax (expense) benefit on stock awards										2,985	3,710	1,262
Dividends paid										(87,395)	(42,555)	(22,404)
Net cash provided by financing activities										1,969,931	2,639,628	1,180,764
Net (decrease) increase in cash and cash equivalents										(82,057)	(19,728)	95,536
Cash and cash equivalents at beginning of year					230,961				250,689	230,961	250,689	155,153
Cash and cash equivalents at end of year		148,904				230,961				148,904	230,961	250,689
Parent Company
Condensed Cash Flow Statements, Captions [Line Items]
Net income										181,506	131,721	112,031
(Equity in undistributed earnings of subsidiary)										(180,370)	(137,576)	(102,472)
Contribution in stock to charitable foundation										0	10,000	0
Gain on securities transactions										1,682	145	89
Decrease in other assets										2,107	2,227	2,235
Increase in other liabilities										4,927	525	1,834
Net cash provided by operating activities										9,852	7,042	13,717
Capital contributed to the Bank										0	(1,074,947)	0
Cash received net of cash paid for acquisition										0	48	738
Purchases of other investments available-for-sale										0	(493)	(668)
Redemption of equity securities available-for-sale										2,700	467	280
Principal collected on ESOP loan										2,062	3,093	1,101
Cash received from MHC for merger										0	11,307	0
Net cash used in investing activities										4,762	(1,060,525)	1,451
Loan to ESOP										0	(66,553)	0
Proceeds from issuance of common stock										0	2,149,893	0
Proceeds from sale of treasury stock										0	38,227	6,916
Purchase of treasury stock										(382,922)	(13,523)	(1,531)
Net tax (expense) benefit on stock awards										2,985	3,710	1,262
Dividends paid										(87,395)	(42,555)	(22,404)
Net cash provided by financing activities										(467,332)	2,069,199	(15,757)
Net (decrease) increase in cash and cash equivalents										(452,718)	1,015,716	(589)
Cash and cash equivalents at beginning of year					$ 1,022,231				$ 6,515	1,022,231	6,515	7,104
Cash and cash equivalents at end of year		$ 569,513				$ 1,022,231				$ 569,513	$ 1,022,231	$ 6,515

Selected Quarterly Financial105

Selected Quarterly Financial Data (Summary Of Certain Quarterly Financial Data) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Quarterly Financial Information Disclosure [Abstract]
Interest and dividend income	$ 188,138	$ 186,897	$ 181,529	$ 175,159	$ 171,090	$ 167,058	$ 164,089	$ 158,625	$ 731,723	$ 660,862	$ 545,068
Interest expense	37,322	35,623	32,977	30,717	30,919	29,212	29,326	29,434	136,639	118,891	109,642
Net interest income	150,816	151,274	148,552	144,442	140,171	137,846	134,763	129,191	595,084	541,971	435,426
Provision for loan losses	5,000	5,000	7,000	9,000	11,500	9,000	8,000	9,000	26,000	37,500	50,500
Net interest income after provision for loan losses	145,816	146,274	141,552	135,442	128,671	128,846	126,763	120,191	569,084	504,471	384,926
Non-interest income	8,700	11,306	11,585	8,534	9,874	9,872	10,173	11,942	40,125	41,861	36,571
Non-interest expenses	85,666	85,921	79,836	76,909	73,923	76,584	112,155	77,198	328,332	339,860	245,711
Income before income tax expense	68,850	71,659	73,301	67,067	64,622	62,134	24,781	54,935	280,877	206,472	175,786
Income tax expense	24,448	22,865	26,939	25,120	21,547	23,092	9,596	20,516	99,372	74,751	63,755
Net income	$ 44,402	$ 48,794	$ 46,362	$ 41,947	$ 43,075	$ 39,042	$ 15,185	$ 34,419	$ 181,505	$ 131,721	$ 112,031
Basic and diluted earnings per common share (usd per share)					$ 0.13	$ 0.11	$ 0.04	$ 0.10	$ 0.55	$ 0.38	$ 0.40
Diluted earnings per common share (usd per share)					$ 0.12	$ 0.11	$ 0.04	$ 0.10	$ 0.55	$ 0.38	$ 0.40

Earnings Per Share (Summary of

Earnings Per Share (Summary of Calculations and Reconciliation of Basic to Diluted Earnings Per Share) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Earnings Per Share Reconciliation [Abstract]
Net income	$ 44,402	$ 48,794	$ 46,362	$ 41,947	$ 43,075	$ 39,042	$ 15,185	$ 34,419	$ 181,505	$ 131,721	$ 112,031
Income available to common stockholders, Basic									$ 181,505	$ 131,721	$ 112,031
Income available to common stockholders, Basic, Shares									329,763,527	344,389,259	279,632,558
Basic and diluted earnings per common share (usd per share)					$ 0.13	$ 0.11	$ 0.04	$ 0.10	$ 0.55	$ 0.38	$ 0.40
Effect of dilutive common stock equivalents, Basic, Shares									3,169,921	3,342,312	3,403,286
Income available to common stockholders, Diluted									$ 181,505	$ 131,721	$ 112,031
Income available to common stockholders, Diluted, Shares									332,933,448	347,731,571	283,035,844
Diluted earnings per common share (usd per share)					$ 0.12	$ 0.11	$ 0.04	$ 0.10	$ 0.55	$ 0.38	$ 0.40
Equity awards
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities excluded from computation of diluted earnings per share									18,200,877	142,953	1,937,015

Comprehensive Income (Loss) (Co

Comprehensive Income (Loss) (Components of Comprehensive Income (Loss), Gross and Net Of Tax) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Equity [Abstract]
Net income, Gross	$ 68,850	$ 71,659	$ 73,301	$ 67,067	$ 64,622	$ 62,134	$ 24,781	$ 54,935	$ 280,877	$ 206,472	$ 175,786
Net income, Tax	(24,448)	(22,865)	(26,939)	(25,120)	(21,547)	(23,092)	(9,596)	(20,516)	(99,372)	(74,751)	(63,755)
Net income	$ 44,402	$ 48,794	$ 46,362	$ 41,947	$ 43,075	$ 39,042	$ 15,185	$ 34,419	181,505	131,721	112,031
Change in funded status of retirement obligations, Gross									(2,425)	(8,402)	16
Change in funded status of retirement obligations, Tax									970	3,360	(6)
Change in funded status of retirement obligations									(1,455)	(5,042)	10
Unrealized gain on securities available-for-sale, Gross									(7,982)	9,836	(21,930)
Unrealized gain on securities available-for-sale, Tax									3,049	(3,884)	9,103
Unrealized gain on securities available-for-sale									(4,933)	5,952	(12,827)
Net Loss on Securities reclassified from available for sale to held to maturity, Gross									0	0	(12,243)
Net Loss on Securities reclassified from available for sale to held to maturity, Tax									0	0	5,001
Net Loss on Securities reclassified from available for sale to held to maturity									0	0	(7,242)
Accretion of loss on securities reclassified to held to maturity, Gross									2,448	2,918	1,670
Accretion of loss on securities reclassified to held to maturity, Tax									(1,000)	(1,192)	(682)
Accretion of loss on securities reclassified to held to maturity									1,448	1,726	988
Unrealized gain on security reclassified from held to maturity to available for sale, Gross									0	0	233
Unrealized gain on security reclassified from held to maturity to available for sale,Tax									0	0	(95)
Unrealized gain on security reclassified from held to maturity to available for sale									0	0	138
Reclassification adjustments for losses included in net income, Gross									(1,553)	(233)	(684)
Reclassification adjustments for losses included in net income, Tax									6	95	279
Reclassification adjustment for losses Included in net income									(1,547)	(138)	(405)
Noncredit related component other-than-temporary impairment on security, Gross									0	0	38
Noncredit related component other-than-temporary impairment on security, Tax									0	0	(16)
Noncredit related component other-than-temporary impairment on security									0	0	22
Other-than-temporary impairment accretion on debt securities, Gross									1,802	1,343	2,075
Other-than-temporary impairment accretion on debt securities, Tax									(736)	(549)	(848)
Other-than-temporary impairment accretion on debt securities									1,066	794	1,227
Total other comprehensive income (loss), Gross									(7,710)	5,462	(30,825)
Total other comprehensive income (loss), Tax									2,289	(2,170)	12,736
Total other comprehensive (loss) income									(5,421)	3,292	(18,089)
Total comprehensive income, Gross									273,167	211,934	144,961
Total comprehensive income, Tax									(97,083)	(76,921)	(51,019)
Total comprehensive income									$ 176,084	$ 135,013	$ 93,942

Comprehensive Income (Loss) 108

Comprehensive Income (Loss) (Component of Accumulated Other Comprehensive Loss) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Total accumulated other comprehensive loss, Beginning Balance	$ (22,404)	$ (25,696)
Total accumulated other comprehensive loss, Net change	(5,421)	3,292	$ (18,089)
Total accumulated other comprehensive loss, Ending Balance	(27,825)	(22,404)	(25,696)
Change in funded status of retirement obligations
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Total accumulated other comprehensive loss, Beginning Balance	(10,911)	(5,869)
Total accumulated other comprehensive loss, Net change	(1,455)	(5,042)
Total accumulated other comprehensive loss, Ending Balance	(12,366)	(10,911)	(5,869)
Accretion of loss on securities reclassified to held to maturity
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Total accumulated other comprehensive loss, Beginning Balance	(4,528)	(6,254)
Total accumulated other comprehensive loss, Net change	1,448	1,726
Total accumulated other comprehensive loss, Ending Balance	(3,080)	(4,528)	(6,254)
Unrealized gain on securities available-for-sale
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Total accumulated other comprehensive loss, Beginning Balance	7,851	1,899
Total accumulated other comprehensive loss, Net change	(4,933)	5,952
Total accumulated other comprehensive loss, Ending Balance	2,918	7,851	1,899
Reclassification adjustment for losses included in net income
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Total accumulated other comprehensive loss, Beginning Balance	0	138
Total accumulated other comprehensive loss, Net change	(1,547)	(138)
Total accumulated other comprehensive loss, Ending Balance	(1,547)	0	138
Other-than- temporary impairment accretion on debt securities
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Total accumulated other comprehensive loss, Beginning Balance	(14,816)	(15,610)
Total accumulated other comprehensive loss, Net change	1,066	794
Total accumulated other comprehensive loss, Ending Balance	$ (13,750)	$ (14,816)	$ (15,610)

Comprehensive Income (Loss) (Re

Comprehensive Income (Loss) (Reclassification Adjustment) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Noncredit-related gains on securities not expected to be sold (recognized in other comprehensive income)									$ 0	$ 0	$ 38
Compensation and fringe benefits									186,320	172,068	128,765
Income tax expense	$ 24,448	$ 22,865	$ 26,939	$ 25,120	$ 21,547	$ 23,092	$ 9,596	$ 20,516	99,372	74,751	$ 63,755
Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total before tax									2,362	322
Income tax expense									976	(205)
Income before undistributed earnings of subsidiary									1,386	527
Unrealized gain on securities available-for-sale | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Gain on security transactions									(1,553)	(233)
Change in funded status of retirement obligations | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Adjustment of net obligation									2,512	(175)
Amortization of net obligation or asset									0	25
Amortization of prior service cost									49	125
Amortization of net gain									1,354	580
Compensation and fringe benefits									$ 3,915	$ 555

Subsequent Event (Details)

Subsequent Event (Details) - $ / shares	Feb. 25, 2016	Jan. 28, 2016	Sep. 28, 2012	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Subsequent Event [Line Items]
Dividends declared per share (usd per share)			$ 0.02
Dividends paid per share (usd per share)				$ 0.25	$ 0.12	$ 0.08
Subsequent Event
Subsequent Event [Line Items]
Dividends declared per share (usd per share)		$ 0.06
Dividends paid per share (usd per share)	$ 0.06