Commitments and Contingencies (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013
Summary of minimum rental commitments under operating and capital leases
Remainder of 2013, Operating Leases	$ 1,387
2014, Operating Leases	1,828
2015, Operating Leases	2,088
2016, Operating Leases	2,019
2017, Operating Leases	2,873
2018 and thereafter, Operating Leases	7,255
Minimum lease payments, Operating Leases	17,450
Less amount representing interest, Operating Leases
Net Minimum Payments, Operating Leases	17,450
Remainder of 2013, Capital Leases	238
2014, Capital Leases	42
2015, Capital Leases
2016, Capital Leases
2017, Capital Leases
2018 and thereafter, Capital Leases
Minimum lease payments, Capital Leases	280
Less amount representing interest, Capital Leases	9
Net Minimum Payments, Capital Leases	$ 271

Capital leases future minimum payments due in five years and thereafter.

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Capital leases future minimum payments due in one year.

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Operating leases future minimum payments due in five years and thereafter.

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Operating leases, future minimum payments, due in one year.

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Operating leases future minimum payments interest included in payments.

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Operating leases future minimum payments net minimum payments.

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Amount of minimum lease payments for capital leases.

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Amount of minimum lease payments maturing in the next fiscal year following the latest fiscal year for capital leases.

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Amount of minimum lease payments maturing in the forth fiscal year following the latest fiscal year for capital leases.

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Amount of minimum lease payments maturing in the third fiscal year following the latest fiscal year for capital leases.

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Amount of minimum lease payments maturing in the second fiscal year following the latest fiscal year for capital leases.

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Amount necessary to reduce net minimum lease payments to present value for capital leases.

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Present value of minimum lease payments for capital leases net of executory costs, including amounts paid by the lessee to the lessor for insurance, maintenance and taxes.

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Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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