Income Taxes - Statutory Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Statutory rate
Statutory tax rate (as a percentage)	35.00%	35.00%	35.00%
Reconciliation
Statutory federal expense (35%)	$ 47,378	$ 29,369	$ 23,376
Statutory state income tax expense, net of federal tax benefit	4,611	2,805	2,195
Other	782	316	(314)
Income tax expense	$ 52,771	$ 32,490	$ 25,257

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

+ References

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to tax exempt income, equity in earnings (loss) of an unconsolidated subsidiary, minority noncontrolling interest income (loss), tax holiday, disposition of a business, disposition of an asset, repatriation of foreign earnings, repatriation of foreign earnings jobs creation act of 2004, increase (decrease) in enacted tax rate, prior year income taxes, increase (decrease) in deferred tax asset valuation allowance, and other adjustments.

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