Commitments and Contingent Liabilities - Schedule of Future Minimum Rental Commitments (Details) $ in Thousands	Dec. 31, 2015 USD ($)
Gross Lease Obligations
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
Year ending December 31, 2016	$ 24,613
Year ending December 31, 2017	28,677
Year ending December 31, 2018	27,003
Year ending December 31, 2019	24,367
Year ending December 31, 2020	22,918
Thereafter through December 31, 2031	175,323
Total	302,901
Sublease Income
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
Year ending December 31, 2016	5,116
Year ending December 31, 2017	4,633
Year ending December 31, 2018	4,286
Year ending December 31, 2019	3,630
Year ending December 31, 2020	2,482
Thereafter through December 31, 2031	6,538
Total	26,685
Net Lease Obligations
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
Year ending December 31, 2016	19,497
Year ending December 31, 2017	24,044
Year ending December 31, 2018	22,717
Year ending December 31, 2019	20,737
Year ending December 31, 2020	20,436
Thereafter through December 31, 2031	168,785
Total	$ 276,216

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 10
-Section 55
-Paragraph 40
-Subparagraph (Note 3)
-URI http://asc.fasb.org/extlink&oid=6584154&loc=d3e38371-112697

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 2
-Subparagraph (a)
-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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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41502-112717

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 10
-Section 55
-Paragraph 40
-Subparagraph (Note 3)
-URI http://asc.fasb.org/extlink&oid=6584154&loc=d3e38371-112697

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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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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year 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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