COMMITMENTS, CONTINGENCIES AND OTHER MATTERS (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014 Officers	Dec. 31, 2013	Dec. 31, 2012
COMMITMENTS, CONTINGENCIES AND OTHER MATTERS [Abstract]
Number of principal shareholders and senior executive officers	3
Capital Leases [Abstract]
2015	$ 2.8
2016	0.6
2017	0.3
2018	0
2019	0
2020-2024	0
2025-2029	0
Thereafter	0
Total minimum lease payments	3.7
Less: sublease rental income	0
Lease obligation net of subleases	3.7
Less amount representing interest	0.1
Present value of minimum capital lease payments (including current portion of 2.7)	3.6
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
2015	28.3
2016	26.4
2017	26.0
2018	21.4
2019	19.1
2020-2024	51.7
2025-2029	25.6
Thereafter	8.0
Total minimum lease payments	206.5
Less: sublease rental income	2.5
Lease obligation net of subleases	204.0
Total lease [Abstract]
2015	31.1
2016	27.0
2017	26.3
2018	21.4
2019	19.1
2020-2024	51.7
2025-2029	25.6
Thereafter	8.0
Total minimum lease payments	210.2syx_TotalLeasesFutureMinimumPaymentsDue
Less: sublease rental income	2.5syx_TotalLeaseSubleaseRentalIncome
Lease obligation net of subleases	207.7
Annual rent expense	31.5us-gaap_LeaseAndRentalExpense	34.6us-gaap_LeaseAndRentalExpense	33.4us-gaap_LeaseAndRentalExpense
Related party rent expense	0.9syx_RentExpenseRelatedParty	0.9syx_RentExpenseRelatedParty	0.9syx_RentExpenseRelatedParty
Rent expense net of sublease income	$ 0	$ 0.1	$ 0.2

Amount representing interest belongs to capital lease.

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Represents lease obligation net of subleases related to capital lease.

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Amount of minimum lease payments for capital leases due in the eleventh to fifteenth fiscal years following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of minimum lease payments for capital leases due in the sixth to tenth fiscal years 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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The number of principal shareholders and senior executive officers.

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Amount of required minimum rental payments maturing after the fifteenth fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Amount of required minimum rental payments maturing in the eleventh to fifteenth fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Amount of required minimum rental payments maturing in the sixth to tenth fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Represents lease obligation net of subleases which belongs to operating leases.

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Rental expense incurred for leased assets in a related party transactions.

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

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Amount of minimum lease payments, both for capital and operating leases.

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Amount of minimum lease payments maturing in the Eleventh to Fifteenth fiscal year following the latest fiscal year for total leases.

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Amount of minimum lease payments maturing in the fifth fiscal year following the latest fiscal year, both for capital and operating leases.

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

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Amount of minimum lease payments maturing in the sixth to tenth fiscal year following the latest fiscal year, both for capital and operating leases.

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

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

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Amount of minimum lease payments maturing after the fifteenth fiscal year following the latest fiscal year, both for capital and operating leases.

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Represents lease obligation net of subleases, both for capital and operating leases.

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No definition available.

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- Definition

The total amount of sublease rental income recognized, both for capital and operating leases.

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Amount of minimum lease payments for capital leases.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6455398&loc=d3e45280-112737

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Amount of minimum lease payments for capital leases due 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 minimum lease payments for capital leases due in 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 of minimum lease payments for capital leases due in the fourth 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 minimum lease payments for capital leases due in the third 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 minimum lease payments for capital leases due in the second 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 minimum lease payments for capital leases due after 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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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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Minimum payments receivable in the future under noncancelable subleases.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6455398&loc=d3e45280-112737

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Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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-URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41502-112717

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due 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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Contractually required future rental payments receivable on noncancelable subleasing arrangements.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in 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 of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fourth 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 required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the third 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 required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the second 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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The total amount of sublease rental income recognized during the period that reduces the entity's rent expense incurred under operating leases.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

-Section 55

-Paragraph 40

-Subparagraph (Note 3)

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