Future Minimum Annual Lease Payments under Capital and Operating Leases with Non-cancelable Terms in Excess of One Year (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012
Capital Leases, Lease Obligations
2013	$ 2,958
2014	2,105
2015	1,222
2016	686
2017	362
Thereafter	4
Total future minimum lease obligation	7,337
Operating Leases, Lease Obligations
2013	8,897
2014	7,300
2015	5,528
2016	4,737
2017	3,747
Thereafter	8,832
Total future minimum lease obligation	$ 39,041

Amount of minimum lease payments for capital leases.

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