v2.4.1.9

Investments - Maturity Dates Of Available-For-Sale Securities (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Available-for-Sale Amortized Cost
Due within 1 year, Cost	$ 213us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost	$ 0us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost
Due after 1 year through year 5, Cost	342us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost	729us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost
Due after 5 years through year 10, Cost	0us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost	0us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost
Due after 10 years, Cost	1,158us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost	1,274us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost
Mortgage-backed securities with original maturities of 30 years, cost	820wex_AvailableForSaleSecuritiesDebtMaturitiesThirtyYearsAmortizedCostBasis	867wex_AvailableForSaleSecuritiesDebtMaturitiesThirtyYearsAmortizedCostBasis
Equity securities with no maturity dates, cost	16,612us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateAmortizedCost	13,777us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateAmortizedCost
Total, Cost	19,145us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis	16,647us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis
Available-for-Sale Fair Value
Due within 1 year, Fair Value	211us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue	0us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue
Due after 1 year through year 5, Fair Value	341us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	728us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue
Due after 5 years through year 10, Fair Value	0us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	0us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue
Due after 10 years, Fair Value	1,167us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue	1,182us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue
Mortgage-backed securities with original maturities of 30 years, fair value	810wex_AvailableForSaleSecuritiesDebtMaturitiesThirtyYearsFairValue	839wex_AvailableForSaleSecuritiesDebtMaturitiesThirtyYearsFairValue
Equity securities with no maturity dates, fair value	16,411us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateFairValue	13,214us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateFairValue
Total, Fair Value	$ 18,940us-gaap_AvailableForSaleSecuritiesDebtSecurities	$ 15,963us-gaap_AvailableForSaleSecuritiesDebtSecurities

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- Definition

This item represents the cost of debt securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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Amount after adjustments of available-for-sale debt securities at cost, maturing in the sixth fiscal year through the tenth fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings less cumulative-effect adjustments, and fair value hedge accounting adjustments. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Fair value of available-for-sale debt securities maturing in the sixth fiscal year through the tenth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount after adjustments of available-for-sale debt securities at cost, maturing in the second fiscal year through the fifth fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings less cumulative-effect adjustments, and fair value hedge accounting adjustments. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Fair value of available-for-sale debt securities maturing in the second fiscal year through the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount after adjustments of available-for-sale debt securities at cost, maturing after the tenth fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings less cumulative-effect adjustments, and fair value hedge accounting adjustments. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Fair value of available-for-sale debt securities maturing after the tenth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount after adjustments of available-for-sale debt securities at cost, maturing in the next fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings less cumulative-effect adjustments, and fair value hedge accounting adjustments. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Fair value of available-for-sale debt securities maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of debt securities categorized neither as held-to-maturity nor trading.

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Available-for-sale securities, debt maturities, thirty years, amortized cost basis.

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