Comprehensive Income (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Comprehensive Income
Net income	$ 1,794us-gaap_ProfitLoss	$ 4,790us-gaap_ProfitLoss
Effective portion of unrealized gain (loss) on cash flow hedge	(311)	(12)
Effect of foreign currency translation	(171)	28
Comprehensive income	1,312	4,806
Less: comprehensive income attributable to noncontrolling interest	452	487
Comprehensive income attributable to SP Plus Corporation	860us-gaap_ComprehensiveIncomeNetOfTax	4,319us-gaap_ComprehensiveIncomeNetOfTax
Accumulated Other Comprehensive Income
Balance at the beginning of the period	(205)
Change in other comprehensive income (loss)	(482)
Balance at the end of the period	(687)
Foreign Currency Translation Adjustments
Accumulated Other Comprehensive Income
Balance at the beginning of the period	(530)
Change in other comprehensive income (loss)	(171)
Balance at the end of the period	(701)
Cash flow hedge
Accumulated Other Comprehensive Income
Balance at the beginning of the period	325
Change in other comprehensive income (loss)	(311)
Balance at the end of the period	$ 14

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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income (loss) and other comprehensive income (loss), attributable to noncontrolling interests. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax and reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss), attributable to parent entity.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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Current period translation adjustment net of tax resulting from translating foreign currency financial statements into the reporting currency. Adjustment is reported in other comprehensive income and is not included in determining net income.

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