The remaining $17,000 ($20,000 - $17,000) is taxable in 2013. Enter $20,000 (total withdrawals) on line 15a of Form 1040, and enter $17,000 (taxable withdrawals) on line 15b. If you owe the 10% penalty tax, fill out Form 5329 (Additional Taxes on Qualified Plans (Including IRAs) and Other Tax-Favored Plans) and enter the penalty on line 58.