Deferred tax assets and liabilities result from various temporary differences between the financial statement carrying amount and their  tax basis. Deferred tax assets and liabilities as of December 31, 2013 and 2012 are summarized as follows (in thousands): (1)  Valuation allowance at 12/31/11 was $9.4 million. At December 31, 2013, we had tax net operating loss carry-forwards in various tax jurisdictions of approximately $19.2 million.  Although we cannot be certain that these operating loss carry-forwards will be utilized, we anticipate that we will have sufficient  taxable income in future years to allow us to fully utilize the carry-forwards that are not subject to a valuation allowance as of  December 31, 2013. If unused, those carry-forwards which are subject to expiration may expire during the years 2014 through 2024.  During 2013, $0.2 million of operating loss carry-forwards which carried a full valuation allowance expired unused. We file income tax returns in the U.S. federal jurisdiction, various states and foreign jurisdictions. We are currently undergoing multi- ple examinations in various jurisdictions, and the years 1999 through 2012 remain open for examination in various tax jurisdictions  in which we operate. In some of these jurisdictions we have received notices of audit assessment that could expose the Company to  additional income taxes, including interest and penalty of approximately $14 million in excess of our current estimates. The ultimate  settlement and timing of these additional tax assessments is uncertain but the Company will continue to vigorously defend its return  filing position and does not view the assessments as probable at this time. 2013 2012 Deferred tax assets: Net operating loss carry-forwards $ 5,382 $ 5,866 Tax credit carry-forwards 447 3,123  Reserves 8,305 13,497 Unrealized benefit plan loss 4,684 586 Other 657 5,419 Total deferred tax assets 19,475 28,491 Valuation allowance  (1) (6,087) (7,243) Net deferred tax asset 13,388 21,248 Deferred tax liabilities: Intangibles (3,050) (1,751) Property, plant and equipment (4,494) (5,540) Other (2,301) (3,624) Total deferred tax liabilities (9,845) (10,915) Net deferred income taxes $ 3,543 $ 10,333 2013 2012 Current deferred tax assets $ 8,936 $   8,024 Current deferred tax liabilities (975) (4,138) Long-term deferred tax assets 4,452 13,224 Long-term deferred tax liabilities (8,870) (6,777) Total deferred tax assets (liabilities) $ 3,543  $ 10,333