Leases	9 Months Ended
Sep. 30, 2016
Leases [Abstract]
Leases	Leases The Company finances a portion of its revenue equipment under capital and operating leases and certain terminals under operating leases. Capital Leases (as Lessee) — The Company’s capital leases are typically structured with balloon payments at the end of the lease term equal to the residual value the Company is contracted to receive from certain equipment manufacturers upon sale or trade back to the manufacturers. If the Company does not receive proceeds of the contracted residual value from the manufacturer, the Company is still obligated to make the balloon payment at the end of the lease term. Certain leases contain renewal or fixed price purchase options. The present value of obligations under capital leases is included under "Current portion of capital lease obligations" and "Capital lease obligations, less current portion" in the consolidated balance sheets. As of September 30, 2016, the leases were collateralized by revenue equipment with a cost of $326.2 million and accumulated amortization of $91.5 million. As of December 31, 2015, the leases were collateralized by revenue equipment with a cost of $357.8 million and accumulated amortization of $90.1 million. Amortization of the equipment under capital leases is included in "Depreciation and amortization of property and equipment" in the Company’s consolidated income statements. Operating Leases (as Lessee) — Rent expense related to operating leases was $57.0 million and $59.1 million for the three months ended September 30, 2016 and 2015, respectively. Rent expense related to operating leases was $170.3 million and $180.9 million for the nine months ended September 30, 2016 and 2015, respectively.

Leases

The Company finances a portion of its revenue equipment under capital and operating leases and certain terminals under operating leases.

Capital Leases (as Lessee) — The Company’s capital leases are typically structured with balloon payments at the end of the lease term equal to the residual value the Company is contracted to receive from certain equipment manufacturers upon sale or trade back to the manufacturers. If the Company does not receive proceeds of the contracted residual value from the manufacturer, the Company is still obligated to make the balloon payment at the end of the lease term. Certain leases contain renewal or fixed price purchase options. The present value of obligations under capital leases is included under "Current portion of capital lease obligations" and "Capital lease obligations, less current portion" in the consolidated balance sheets. As of September 30, 2016, the leases were collateralized by revenue equipment with a cost of $326.2 million and accumulated amortization of $91.5 million. As of December 31, 2015, the leases were collateralized by revenue equipment with a cost of $357.8 million and accumulated amortization of $90.1 million. Amortization of the equipment under capital leases is included in "Depreciation and amortization of property and equipment" in the Company’s consolidated income statements.

Operating Leases (as Lessee) — Rent expense related to operating leases was $57.0 million and $59.1 million for the three months ended September 30, 2016 and 2015, respectively. Rent expense related to operating leases was $170.3 million and $180.9 million for the nine months ended September 30, 2016 and 2015, respectively.